Vol.:(0123456789)

Sports Medicine (2020) 50:1785–1812 https://doi.org/10.1007/s40279-020-01317-5

SYSTEMATIC REVIEW

The Effects of Oral Contraceptives on Exercise Performance in Women: A Systematic Review and Meta‑analysis

Kirsty J. Elliott‑Sale1  · Kelly L. McNulty2  · Paul Ansdell2  · Stuart Goodall2  · Kirsty M. Hicks2  · Kevin Thomas2  · Paul A. Swinton3  · Eimear Dolan4

Published online: 14 July 2020 © The Author(s) 2020

AbstractBackground Oral contraceptive pills (OCPs) are double agents, which downregulate endogenous concentrations of oestradiol and progesterone whilst simultaneously providing daily supplementation of exogenous oestrogen and progestin during the OCP-taking days. This altered hormonal milieu differs significantly from that of eumenorrheic women and might impact exercise performance, due to changes in ovarian hormone-mediated physiological processes.Objective To explore the effects of OCPs on exercise performance in women and to provide evidence-based performance recommendations to users.Methods This review complied with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A between-group analysis was performed, wherein performance of OCP users was compared with naturally menstruating women, and a within-group analysis was conducted, wherein performance during OCP consumption was compared with OCP withdrawal. For the between-group analysis, women were phase matched in two ways: (1) OCP withdrawal versus the early follicular phase of the menstrual cycle and (2) OCP consumption versus all phases of the menstrual cycle except for the early follicular phase. Study quality was assessed using a modified Downs and Black Checklist and a strategy based on the recommendations of the Grading of Recommendations Assessment Development and Evaluation working group. All meta-analyses were conducted within a Bayesian framework to facilitate probabilistic interpretations.Results 42 studies and 590 participants were included. Most studies (83%) were graded as moderate, low or very low quality, with 17% achieving high quality. For the between-group meta-analysis comparing OCP users with naturally menstruating women, posterior estimates of the pooled effect were used to calculate the probability of at least a small effect (d ≥ 0.2). Across the two between-group comparison methods, the probability of a small effect on performance favouring habitual OCP users was effectually zero (p < 0.001). In contrast, the probability of a small effect on performance favouring naturally menstruating women was moderate under comparison method (1) (d ≥ 0.2; p = 0.40) and small under comparison method (2) (d ≥ 0.2; p = 0.19). Relatively large between-study variance was identified for both between-group comparisons ( �0.5 = 0.16 [95% credible interval (CrI) 0.01–0.44] and �0.5 = 0.22 [95% CrI 0.06–0.45]). For the within-group analysis comparing OCP consumption with withdrawal, posterior estimates of the pooled effect size identified almost zero probability of a small effect on performance in either direction (d ≥ 0.2; p ≤ 0.001).Conclusions OCP use might result in slightly inferior exercise performance on average when compared to naturally menstru-ating women, although any group-level effect is most likely to be trivial. Practically, as effects tended to be trivial and vari-able across studies, the current evidence does not warrant general guidance on OCP use compared with non-use. Therefore, when exercise performance is a priority, an individualised approach might be more appropriate. The analysis also indicated that exercise performance was consistent across the OCP cycle.

Joint first authors: Kirsty J. Elliott-Sale and Kelly L. McNulty.

Electronic supplementary material The online version of this article (https ://doi.org/10.1007/s4027 9-020-01317 -5) contains supplementary material, which is available to authorized users.

Extended author information available on the last page of the article

1 IntroductionSex hormones are one of the main determinants of biological sex [1]. During adulthood, levels of testosterone, the pre-dominant male sex hormone, remain consistent in men [2], whilst concentrations of oestrogen and progesterone, the pre-vailing female sex hormones, undergo circamensal changes

http://orcid.org/0000-0003-1122-5099http://orcid.org/0000-0001-6176-7983http://orcid.org/0000-0001-7542-1107http://orcid.org/0000-0001-9029-2171http://orcid.org/0000-0002-5057-9191http://orcid.org/0000-0003-2973-5337http://orcid.org/0000-0001-9663-0696http://orcid.org/0000-0002-1018-7601http://crossmark.crossref.org/dialog/?doi=10.1007/s40279-020-01317-5&domain=pdfhttps://doi.org/10.1007/s40279-020-01317-5

1786 K. J. Elliott-Sale et al.

Key Points

When compared with a natural menstrual cycle, oral contraceptive pill (OCP) use might result in slightly inferior exercise performance, although any group level effect is most likely to be trivial, and as such from a practical perspective, the current evidence does not warrant general guidance on OCP use compared with non-use.

Exercise performance appeared relatively consistent across the OCP cycle, suggesting that different guidance is not warranted for OCP-taking days versus non-OCP taking days.

In the case of sportswomen who are focussing on performance, it is recommended that an individualised approach is sought, based on each athlete’s response to OCP use.

in women [3], marking one of the major differences between sexes. Moreover, the eumenorrheic menstrual cycle is sus-ceptible to internal (e.g., amenorrhea, oligomenorrhea and menorrhagia) and external (e.g., hormonal contraceptives) perturbations, highlighting the diversity in ovarian hormone profiles between women. In a recent audit of 430 elite female athletes, Martin et al. [4] showed that 213 athletes were hor-monal contraceptive users, meaning that almost half of the population surveyed did not have a eumenorrheic menstrual cycle. Of these, 145 (68%) athletes reported taking oral con-traceptive pills (OCPs), making them the most common type of hormonal contraceptive used and the second most com-mon hormonal profile, after non-hormonal contraceptive users. These differences in endocrine profiles, between men and women, and amongst women (i.e., hormonal contracep-tive users and non-users), highlight the need for sex-specific consideration within sport and exercise science.

Combined OCPs significantly reduce endogenous con-centrations of 17 beta oestradiol and progesterone [5], when compared to the mid-luteal phase of the menstrual cycle, a stage when endogenous oestradiol and progesterone are relatively high. The exogenous oestrogens and progestins act via negative feedback on the gonadotrophic hormones, resulting in the chronic downregulation of the hypothalamic-pituitary-ovarian axis. Most combined, monophasic OCPs are second generation OCPs, containing low to standard doses of ethinyl oestradiol and either levonorgestrel, nore-thisterone, desogestrel or gestodene, delivered in a fixed amount every day for 21 OCP taking days (i.e., consump-tion phase), followed by 7 OCP free days (i.e., withdrawal phase) [6]. In some countries, rather than a consumption

and withdrawal approach, there are 21 active OCP days and 7 inactive OCP days. There are many types of OCPs with different compositions and potencies; for a comprehensive overview of hormonal contraceptives and OCPs please see Elliott-Sale and Hicks [6]. Overall, OCP use results in four distinct hormonal environments: (1) a downregulated endog-enous oestradiol profile of ≈ 60 pmol·L−1 for 21 days that rises during the 7 OCP free days to ≈ 140 pmol·L−1; (2) a chronically downregulated endogenous progesterone profile of ≈ 5 nmol·L−1; (3) a daily surge of synthetic oestrogen and progestin that peaks within 1 h after ingestion [from ≈ 2 to ≈ 6 pg·mL−1], with baseline values accumulating slightly from ≈ 2 to ≈ 3 pg·mL−1 over the 21 OCP-taking days; (4) 7 exogenous hormone-free days [7]. These profiles, reflecting OCP consumption and withdrawal, are referred to as pseudo-phases, as they are “artificial” phases in comparison with the phases of the physiological menstrual cycle.

Aside from fertility control, OCPs are also used to alle-viate the symptoms of dysmenorrhoea and menorrhagia; reduce the occurrence of premenstrual tension, symptomatic fibroids, functional ovarian cysts and benign breast disease; and decrease the risk of ovarian and endometrial cancer and pelvic inflammatory disease [8]. Furthermore, athletic popu-lations have reported strategically using OCPs to manipulate the timing of, or omit entirely, the often-perceived incon-venient withdrawal bleed that occurs during the 7 OCP free days, using back-to-back OCP cycles [4, 9, 10]. Reliable and reversible contraception, along with the means to alleviate the side-effects associated with the eumenorrheic menstrual cycle, such as cramps/pain, bloating and headaches, and the ability to eliminate unpredictable menstruation, make OCPs a desirable option for many athletes.

Despite the prevalence of OCP use in athletic popula-tions [4], the effects of OCPs on exercise performance are poorly understood. Although many experimental studies [11–13], numerous narrative and systematic reviews [14, 15] and books [16, 17] have addressed this topic, few in the area of sport and exercise science (e.g., athletes, coaches, practitioners or researchers) truly understand the implications of OCP use on exercise performance, as previous research has shown conflicting findings on the directional effects of OCPs on outcomes such as muscle function [18, 19], aerobic and anaerobic [20–22] capacity and performance-based tests [23, 24]. As such, it is not possible to provide useful guidance to either the sport-ing or research community on how to work with athletes or participants using OCPs. Accordingly, the aim of this review was to investigate the effects of OCP use on exer-cise performance in women by making a between group comparison of OCP users and non-users (i.e., naturally menstruating counterparts) and a within group compar-ison of OCP consumption and withdrawal. This is the first meta-analysis on the effects of OCPs on exercise

1787Oral Contraceptives and Exercise Performance

performance. Additionally, this review is the first of its kind to appraise the quality of previous studies using robust assurance tools.

2 Methods

2.1 Design

The review was designed in accordance with the Pre-ferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA; Electronic Supplementary Material Appendix S1) guidelines [25], and consideration of the Population, Intervention, Comparator, Outcomes and Study design (PICOS, Table 1) was used to determine the parameters within which the review was conducted.

2.2 Study Search and Selection

PubMed, The Cochrane Central Register of Controlled Tri-als (CENTRAL), ProQuest and SPORTDiscus were system-atically searched using the search terms “oral contracep-tives” AND “athletic performance”; “sports performance”; “muscle”; “skeletal muscle”; “strength”; “force”; “mus-cular strength”; “muscular force”; “power”; “anaerobic”; “anaerobic power”; “anaerobic performance”; “anaerobic capacity”; “aerobic”; “aerobic capacity”; “aerobic power”; “aerobic performance”; “endurance”; “endurance capacity”; “endurance power”; “endurance performance”; “fatigue”; “recovery”. Searches were limited to humans, English, and

females and no date restriction was applied. Only original research articles were considered for inclusion and review articles or conference abstracts were excluded. An example electronic search strategy for PubMed, including limits, can be found in Electronic Supplementary Material Appendix S2. All searches were conducted in January 2019 by KES. Three independent reviewers (KES, KLM and KMH) under-took a three-phase screening strategy: title and abstract, full-text screen and full-text appraisal. The search was updated in April 2020 using the same search criteria and screening strategy. These papers were subsequently included within the review and the meta-analysis was updated.

2.3 Data Extraction and Quality Appraisal

Data were extracted by ED using a pre-piloted extraction sheet. When data were presented in graphical, and not in numerical format, DigitizeIt software (Version 2.3, Digi-tizeIt, Germany) was used to convert the data. The quality of each review outcome (defined as each of the statistical models undertaken) was assigned using a strategy based on the recommendations of the Grading of Recommenda-tions Assessment Development and Evaluation (GRADE) working group [26]. This approach considers the quality of research outcomes in a systematic review according to five domains, namely risk of bias, directness, consistency, precision and evidence of publication bias. Risk of bias and directness were assessed at the individual study level with mode ratings used to categorise whole outcomes. The meta-analysis results were subsequently used to ascertain the consistency, precision and risk of publication bias for

Table 1 Population, intervention, comparator, outcomes and study design (PICOS) criteria

OCP oral contraceptive pill

Population Healthy women aged 18–40 years were considered for inclusion in this study. No restrictions on activity level or training status were placed

Intervention All participants were required to take an OCP, either habitually or experimentally. “Habitual” was defined as OCP use prior to the commencement of the study and not for the purposes of the study. “Experimentally” was defined as starting OCP use for the purposes of the study. All forms of OCPs were considered for use within this review

Comparator Four broad types of comparisons were considered: (1) Between group comparison of habitual OCP users to naturally menstruat-ing women. Women were phase matched in two ways for this comparison: (i) OCP withdrawal versus the early follicular phase of the menstrual cycle and (ii) OCP consumption versus all other phases of the menstrual cycle except for the early follicular phase; (2) within group comparison of OCP consumption with the hormone-free withdrawal phase; (3) comparison of active OCP use with non-use (e.g ., within-group comparison of women who were habitual users or non-users who stopped/started taking OCP for the purpose of the study); (4) randomised controlled trials of OCPs versus placebo intake ( e.g ., between group comparison of naturally menstruating women who were randomly assigned to either an OCP or placebo pill)

Outcomes The primary outcome was to determine any differences in exercise performance, based on the comparisons described above. ‘Exercise performance’ referred to outcomes stemming from: workload, time to completion and exhaustion, mean, peak out-puts, rate of production and decline and maximum oxygen uptake (a full list of considered outcomes can be found in Table 2). Although maximum oxygen uptake is not a performance test, this physiology-based outcome was included as it is widely used as an indicator of performance and is often used to describe the fitness of participants. Different exercise outcomes, broadly categorised as endurance and strength were considered. All exercise outcomes were extracted, and effect size duplication of multiple outcomes from the same test accounted for within the statistical analysis, as described in Sect. 2.4

Study design Any study design that included the information described above was considered for inclusion

1788 K. J. Elliott-Sale et al.

each outcome. Each individual study was initially appraised using a modified version of the Downs and Black Checklist [27], which was specifically tailored for use in this review (see Electronic Supplementary Material Appendix S3). The modified quality appraisal checklist comprised 15 out-comes, and had a maximum attainable score of 16, with all studies classified as being of high (H; 14–16), moder-ate (M; 10–13), low (L; 6–9) or very low (VL; 0–5) qual-ity. The results of this assessment were used to assign an a priori quality rating to each outcome. This a priori rating was either maintained, or downgraded a level, based on the response to two questions that were considered key to the directness of the research design, i.e., Question 1: was the natural menstrual cycle phase confirmed using appropriate biochemical outcomes? Question 2: was the type of OCP described to the level of detail required for categorisation or replication? With regards to Question 1, for studies with OCP groups only, biochemical confirmation was not deemed necessary, as OCP users do not have cyclical fluctuations in endogenous sex hormones, in which case the a priori score was maintained rather than downgraded. This rating was then either maintained, or downgraded another level based on whether the results obtained were consistent (determined by visual inspection of effect size estimates and the degree of credible intervals [CrI] overlap); precise (with outcomes downgraded if they were based on < 5 data points) and whether or not publication bias was evidence (determined using Egger’s test along with visual inspection of funnel plots as described in Sect. 2.4). The proportion of studies in each category was reported, with the mode considered to represent the overall quality rating for each individual review outcome. Two independent reviewers (KES and KMH) veri-fied the data extraction and quality appraisal.

2.4 Data Analysis

Data were extracted from studies comprising both between group and within group designs. Pairwise effect sizes were calculated by dividing mean differences by pooled standard deviations. At the study level, variance of effect sizes were calculated according to standard distributional assumptions [28]. All meta-analyses were conducted within a Bayes-ian framework enabling the results to be interpreted more intuitively compared to a standard frequentist approach through use of subjective probabilities [29]. With a Bayes-ian framework, dichotomous interpretations of the results of a meta-analysis with regards to the presence or absence of an effect (e.g., with p values) can be avoided, and greater emphasis placed on describing the most likely values for the average effect and addressing practical questions such as the probability the average effect is beyond a certain threshold [29]. The Bayesian framework is also particularly suited to hierarchical models and sharing information within and

across studies to improve estimates [29]. In the present meta-analysis, three-level hierarchical models were conducted to account for covariance in multiple outcomes presented in the same study [30]. Initial models were conducted includ-ing both strength and endurance outcomes with a regression coefficient assessing difference in the average effects. Where no evidence of a difference was identified, the model was re-run combining both categories of outcomes to increase data to better estimate model parameters. Given the expec-tation of relatively small effect sizes, an a priori threshold of ± 2 was identified for outliers. Primary analyses were completed with outliers removed but results also presented from the full complement of studies as sensitivity analyses. Additionally, sensitivity analyses were conducted on data obtained from studies categorised as “high” or “moderate” in quality. Inferences from all analyses were performed on posterior samples generated by Hamiltonian Markov Chain Monte Carlo with Bayesian 95% CrIs constructed to enable probabilistic interpretations of parameter values [29]. Inter-pretations were based on visual inspection of the posterior sample, the median value (ES0.5: 0.5-quantile) and 95% CrIs. Cohen’s [31] standard threshold value of 0.2 was used to describe effect size as small, and values between 0 and 0.2 were described as trivial. Analyses were performed using the R wrapper package brms, which was interfaced with Stan to perform sampling [32]. Convergence of parameter esti-mates was obtained for all models with Gelman–Rubin R-hat values below 1.1 [33]. Additional sensitivity analyses were conducted by restricting the analysis to studies that included exercise performance as the primary study outcome. Assess-ment of publication bias using Egger’s multilevel test with effect sizes regressed on inverse standard errors [34] identi-fied no evidence of publication bias with median absolute intercept values less than 0.1 across all analyses.

2.5 Rationale for Between Group Comparisons

For the between group analyses of habitual OCP users to naturally menstruating women, the OCP withdrawal phase [days 1–7] was compared with the early follicular phase [days 1–5] of the menstrual cycle and the OCP consump-tion phase [days 8–28] was compared with all phases of the menstrual cycle [days 6–28] except the early follicular phase [days 1–5]. The OCP withdrawal phase was com-pared with the early follicular phase as during the with-drawal phase OCP users experience a withdrawal bleed and during the early follicular phase of the menstrual cycle women experience menstruation. In addition, dur-ing both phases endogenous concentrations of oestrogen and progesterone are comparably low. During the remain-der of the menstrual cycle, endogenous concentrations of oestrogen and progesterone change over time (e.g., the mid-cycle peak in oestrogen and the mid-luteal rise in

1789Oral Contraceptives and Exercise Performance

progesterone and oestrogen) and there is large variation in endogenous concentrations of oestrogen and progesterone as a result of different OCP formulations. As such, it is difficult to make meaningful comparisons during these phases and this could be considered a limiting factor of any meta-analysis making between group comparisons of naturally menstruating women and OCP users. To reduce the impact of this limitation, a sensitivity analy-sis was completed on the between group design data to better match the physiological menstrual cycle and OCP pseudo-phases. This was achieved by mapping days 1–5, 12–16 and 19–23 from both cycles, which correspond with the early follicular, ovulatory and mid-luteal phases in a natural menstrual cycle and represents the following hormonal profiles: low oestrogen and progesterone, high oestrogen and low progesterone and high progesterone and medium oestrogen. As such, this meta-analysis (1) compared the two most stable phases of the OCP and menstrual cycles in the first between group analyses; (2) compared the two least stable phases of the OCP and menstrual cycles in the second between group analysis; and (3) performed an additional sensitivity analysis to better match the OCP and menstrual phases.

3 Results

3.1 Study Characteristics

Figure 1 shows the studies identified and selected by the search strategy. Details of the included studies are shown in Table 2. In total 42 studies [5, 13, 18–20, 22–24, 35–68] and 590 participants were included.

Methodological quality at the level of the individual study is shown in Fig. 2; 83% of the studies were graded as M, L or very low VL, with 17% achieving H quality. Specifically, 4 studies were graded as VL, 10 as L, 21 as M and 7 as H quality.

3.2 Between Group Analyses of Habitual Oral Contraceptive Users Compared to Naturally Menstruating Women

Thirty of the included studies (combined quality rating = M; specifically 20% H; 37% M; 30% L; 13% VL) generated 151 effects sizes from research designs comparing habitual OCP users with naturally menstruating women. The data were collected from 597 participants (habitual OCP n = 303, naturally menstruating n = 294) with studies comprising a mean group size of 10 (range n = 5–25).

3.2.1 Oral Contraceptive Pill Withdrawal [Days 1–7] Versus the Early Follicular Phase [Days 1–5] of the Menstrual Cycle

Three outliers were identified with effect sizes greater than + 2, and were removed from the analysis, leaving a total of 49 effect sizes (26 endurance, 23 strength) from 18 studies (combined quality rating = M; specifically 17% H; 33% M; 28% L; 22% VL; habitual OCP n = 176, naturally menstruating n = 169). The three-level hierarchical model indicated a trivial effect with the median value associating greater performances with naturally menstruating women (ES0.5 = 0.18 [95% CrI − 0.02 to 0.37]; Fig. 3). Relatively large between-study standard deviation was identified ( �0.5 = 0.16 [95% CrI 0.01–0.44]) with estimates indicating moderate intraclass correlation (ICC0.5 = 0.42 [95% CrI 0.00–0.80]) due to analysis of multiple outcomes reported within studies. Pooling of strength and endurance outcomes was conducted as no evidence was obtained that indicated a differential effect between the performance categories (ES0.5/Endurance-Strength = 0.04 [95% CrI − 0.41 to 0.43]). Poste-rior estimates of the pooled effect size identified a moderate probability of a small effect favouring naturally menstruating women in the early follicular phase of the menstrual cycle (d ≥ 0.2; p = 0.404) and effectually a zero probability favour-ing habitual OCP women (d ≤ − 0.2; p = 0.001). Inclusion of outliers within the model substantially increased the aver-age effect size (ES0.5 = 0.34 [95% CrI − 0.04 to 0.72]) and between study variance ( �0.5 = 0.70 [95% CrI 0.24–1.23]).

3.2.2 Oral Contraceptive Pill Consumption [Days 8–28] Versus all Phases of the Menstrual Cycle [Days 6–28] Except the Early Follicular Phase [Days 1–5]

Eleven outliers were identified with effect sizes greater than + 2, and were removed from the analysis, leaving a total of 88 effect sizes (53 endurance, 35 strength) from 24 stud-ies (combined quality rating = M; specifically 21% H; 42% M; 25% L; 13% VL; habitual OCP n = 244 habitual OCP, naturally menstruating n = 230). The three-level hierarchi-cal model indicated a trivial effect with the median value associating greater performances obtained in the naturally menstruating women (ES0.5 = 0.13 [95% CrI − 0.05 to 0.28]; Fig. 4). Relatively large between study variance was identi-fied �0.5 = 0.22 [95% CrI 0.06–0.45] with central estimates indicating very low intraclass correlation ICC0.5 = 0.08 [95% CrI 0.0–0.61] due to analysis of multiple outcomes reported within studies. Pooling of strength and endurance outcomes was conducted as no evidence was obtained that indicated a differential effect between the performance categories (ES0.5/Endurance-Strength = 0.02 [95% CrI − 0.25 to

1790 K. J. Elliott-Sale et al.

Tabl

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Ove

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c-tio

n—S

Mod

erat

e

1791Oral Contraceptives and Exercise Performance

Tabl

e 2

(con

tinue

d)

Stud

yA

imPa

rtici

pant

hea

lth a

nd

train

ing

stat

usSt

udy

desi

gnO

ral c

ontra

cept

ive

pill

type

Eum

enor

rhei

c gr

oup

desc

riptio

nEx

erci

se o

utco

mes

Qua

lity

ratin

g

Bem

ben

et a

l. [3

8]To

mea

sure

the

influ

-en

ce o

f OC

P on

gr

owth

hor

mon

e an

d pr

olac

tin re

spon

ses

and

on e

nerg

y su

bstra

te u

tiliz

atio

n du

ring

prol

onge

d su

bmax

imal

exe

rcis

e

Hea

lthy,

mod

erat

ely

activ

e w

omen

(2

5.1 ±

1.4

year

s)

Para

llel g

roup

, obs

er-

vatio

nal,

sing

le-

mea

sure

Mul

ti or

mon

opha

sic

OC

Ps c

onta

inin

g 35

 µg

of o

estro

gen

(Orth

o N

ovum

10/

11,

7–7–

7, 1

/35

and

Dem

ulen

)

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

(cyc

les

rang

ing

from

28

to

35 d

ays i

n le

ngth

), fo

r one

yea

r prio

r to

the

study

, tes

ted

at th

e EL

, ML

and

LL p

hase

s, ve

rified

by

BB

T an

d se

rum

pr

oges

tero

ne

̇ VO

2 pea

k (m

l·kg·

min

−1 )

and

ab

solu

te w

orkl

oad

(m·m

in−

1 ) m

easu

red

durin

g an

incr

emen

-ta

l run

to v

oliti

onal

fa

tigue

—E

Low

Bus

hman

et a

l. [3

9]To

mea

sure

the

effec

t of

men

strua

tion

and

OC

P on

pow

er

perfo

rman

ce

Hea

lthy,

mod

erat

ely

activ

e w

omen

(2

1.6 ±

2.6

year

s)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

2 pa

rtici

pant

s too

k a

mon

opha

sic

and

15 a

m

ultip

hasi

c O

CP

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

teste

d at

the

EF a

nd E

L ph

ases

, ver

ified

by

BB

T an

d ur

inar

y ov

ulat

ion

dete

ctio

n te

st

Estim

ated

̇ VO

2 pea

k (m

l·kg·

min

−1 )

m

easu

red

from

th

e Fo

restr

y St

ep

Test—

E; p

eak

pow

er

(W o

r W·k

g−1 )

, an

aero

bic

capa

city

(W

or W

·kg−

1 ) a

nd

pow

er d

eclin

e (W

or

W·k

g−1 )

mea

sure

d by

th

e W

inga

te te

st—E

and

anae

robi

c po

wer

(k

gm·s−

1 ) m

easu

red

in th

e M

arga

ria K

ala-

men

test—

E

Low

/ver

y lo

w

Cas

azza

et a

l. [2

0]To

mea

sure

the

effec

ts

of M

C p

hase

and

tri

phas

ic O

CP

use

on p

eak

exer

cise

ca

paci

ty

Hea

lthy,

hab

itual

ly

activ

e w

omen

who

w

ere

not c

ompe

titiv

e at

hlet

es (2

5.5 ±

1.5

year

s)

With

in g

roup

, int

er-

vent

ion

(OC

P),

repe

ated

mea

sure

s

Stan

dard

ized

trip

hasi

c O

CP

(day

s 1–7

: 0.

035 

mg

ethi

nyle

-str

adio

l and

0.1

8 m

g no

rges

timat

e; d

ays

8–14

: 0.0

35 e

thin

yle-

strad

iol a

nd 0

.215

no

rges

timat

e; d

ays

15–2

1: 0

.035

 mg

ethi

nyle

strad

iol a

nd

0.25

 mg

norg

esti-

mat

e, d

ays 2

2–28

: pl

aceb

o pi

ll)

Wom

en w

ith a

se

lf-re

porte

d na

tura

l mon

thly

M

C (2

2–32

 day

s in

leng

th) f

or a

t lea

st 6 

mon

ths,

teste

d du

r-in

g th

e LF

and

ML

phas

es, v

erifi

ed b

y a

urin

ary

ovul

atio

n de

tect

ion

test

and

seru

m o

estro

gen

and

prog

este

rone

Peak

̇ VO

2 (L·

min

−1 )

, po

wer

(W) a

nd ti

me

to e

xhau

stion

(min

) m

easu

red

durin

g an

in

crem

enta

l cyc

le to

vo

litio

nal f

atig

ue—

E

Mod

erat

e

1792 K. J. Elliott-Sale et al.

Tabl

e 2

(con

tinue

d)

Stud

yA

imPa

rtici

pant

hea

lth a

nd

train

ing

stat

usSt

udy

desi

gnO

ral c

ontra

cept

ive

pill

type

Eum

enor

rhei

c gr

oup

desc

riptio

nEx

erci

se o

utco

mes

Qua

lity

ratin

g

de B

ruyn

-Pre

vost

et a

l. [4

0]To

mea

sure

the

effec

ts o

f OC

P an

d eu

men

orrh

eic

MC

on

the

phys

iolo

gica

l re

spon

se to

aer

obic

an

d an

aero

bic

endu

r-an

ce te

sts

Wom

en (2

2 ± 2.

2 ye

ars)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

No

info

rmat

ion

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

, tes

ted

durin

g th

e EF

, ovu

la-

tory

and

LL

phas

es,

verifi

ed b

y B

BT

̇ VO

2 pea

k (L

·min

−1 )

an

d w

orki

ng c

apac

-ity

at a

hea

rt ra

te

of 1

70 b

pm (W

) m

easu

red

usin

g an

in

crem

enta

l cyc

le to

vo

litio

nal f

atig

ue—

E,

and

max

imal

ped

al

time

(s) d

urin

g a

fixed

load

(350

 W)

anae

robi

c en

dura

nce

test—

E

Very

low

Dra

ke e

t al.

[41]

To m

easu

re th

e eff

ect o

f OC

P an

d eu

men

orrh

eic

MC

on

ele

ctro

myo

grap

hy

and

mec

hano

myo

gra-

phy

durin

g is

omet

ric

mus

cle

cont

ract

ions

Hea

lthy

wom

en (2

4 ± 1

year

s) w

ho w

ere

not

invo

lved

in a

n ex

er-

cise

pro

gram

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

No

info

rmat

ion

Wom

en w

ith a

se

lf-re

porte

d na

tura

l mon

thly

M

C (2

6–32

 day

s in

leng

th) t

este

d at

the

EF, L

F, o

vula

tion

and

EL, v

erifi

ed u

sing

ur

inar

y ov

ulat

ion

dete

ctio

n te

st

Max

imal

and

sub-

max

imal

isom

etric

ex

tens

or a

nd fl

exor

co

ntra

ctio

n at

100

, 75

, 50

and

25%

of

max

imal

torq

ue

(N m

)—S

Very

low

Eken

ros e

t al.

[42]

To m

easu

re th

e eff

ect

of O

CP

and

eum

enor

-rh

eic

MC

on

mus

cle

stren

gth

and

hop

perfo

rman

ce

Hea

lthy

wom

en

(26.

7 ± 3.

8 ye

ars)

w

ho w

ere

enga

ged

in m

oder

ate

to h

igh

leve

ls o

f rec

reat

iona

l ac

tivity

With

in-g

roup

, int

er-

vent

ion,

repe

ated

m

easu

res

Low

dos

e m

onop

hasi

c O

CPs

con

tain

ing

ethi

nyl o

estra

diol

(2

0–35

 μg)

com

bine

d w

ith d

iffer

ent p

ro-

gesto

gen

(Lev

onor

g-es

trel,

Nor

gesti

mat

e,

Dro

spire

none

, Des

-og

estre

l, N

oret

ister

-on

e an

d Ly

nestr

enol

)

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

who

ha

d no

t bee

n ta

king

an

y ho

rmon

e-co

n-ta

inin

g co

ntra

cept

ive

for a

t lea

st th

ree

mon

ths p

rior t

o th

e stu

dy, t

este

d du

ring

the

EF, o

vula

tory

and

M

L ph

ases

, ver

ified

us

ing

urin

ary

ovul

a-tio

n de

tect

ion

test

and

seru

m o

estro

gen

and

prog

este

rone

Peak

isok

inet

ic k

nee

exte

nsor

stre

ngth

(N

m)—

S, h

andg

rip

stren

gth

(kg)

—S

and

jum

p he

ight

dur

ing

the

one

leg

hop

test

(cm

)—S

Mod

erat

e

1793Oral Contraceptives and Exercise Performance

Tabl

e 2

(con

tinue

d)

Stud

yA

imPa

rtici

pant

hea

lth a

nd

train

ing

stat

usSt

udy

desi

gnO

ral c

ontra

cept

ive

pill

type

Eum

enor

rhei

c gr

oup

desc

riptio

nEx

erci

se o

utco

mes

Qua

lity

ratin

g

Ellio

tt et

 al.

[5]

To m

easu

re th

e eff

ect

of O

CP

and

MC

on

max

imum

forc

e pr

oduc

tion

Hea

lthy

wom

en (2

2 ± 4

year

s) w

ho w

ere

sede

ntar

y (d

efine

d as

no

t bei

ng in

volv

ed in

a

stren

gth

or a

erob

ic

train

ing

prog

ram

fo

r the

pre

viou

s 6 

mon

ths)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Com

bine

d m

onop

hasi

c O

CPs

(Mic

rogy

non,

B

revi

nor,

Ova

rnet

te,

Mar

valo

n, C

ilest)

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

(mea

n cy

cle

leng

th o

f 29

 day

s) w

ho w

ere

not t

akin

g an

y ho

rmon

al b

ased

con

-tra

ctio

n fo

r 6 m

onth

s pr

ior t

o th

e stu

dy,

teste

d du

ring

the

EF a

nd M

L ph

ases

, ve

rified

by

BB

T,

urin

ary

ovul

atio

n de

tect

ion

test

and

seru

m o

estro

gen

and

prog

este

rone

Max

imal

vol

unta

ry

isom

etric

forc

e of

the

first

dors

al in

tero

s-se

us m

uscl

e (N

)—S,

is

okin

etic

ext

en-

sion

and

flex

ion

of

the

quad

ricep

s and

ha

mstr

ing

mus

cles

at

1.0

4. 2

.09

and

4.19

 rad/

S (N

 m)—

S,

and

isom

etric

ext

en-

sion

and

flex

ion

(N m

)—S

Mod

erat

e

Gia

com

oni a

nd F

al-

gaire

tte [4

3]To

mea

sure

the

effec

t of

tim

e of

day

an

d O

CP

use

on

max

imum

ana

erob

ic

pow

er

Phys

ical

edu

catio

n stu

dent

s (22

.8 ±

2.8

year

s)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Com

bine

d m

onop

hasi

c O

CP

(0.0

2–0.

03 m

g et

hiny

lestr

adio

l and

0.

150 

mg

des-

oges

trel o

r 0.0

75 m

g ge

stode

ne)

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

lasti

ng

25–3

1 da

ys in

leng

th,

who

had

not

use

d an

y O

CP

for a

t lea

st 4 

mon

ths b

efor

e en

terin

g th

e stu

dy,

teste

d du

ring

the

LF

and

ML,

ver

ified

by

seru

m o

estro

gen

and

prog

este

rone

leve

ls

Peak

vel

ocity

(rpm

)—E,

pea

k fo

rce

(kg)

—S

and

peak

pow

er

(W)—

E, m

easu

red

durin

g a

forc

e ve

loc-

ity te

st

Mod

erat

e

Gia

com

oni e

t al.

[22]

To m

easu

re th

e eff

ect

of O

CP

and

eum

enor

-rh

eic

MC

on

anae

ro-

bic

perfo

rman

ce

Phys

ical

edu

catio

n stu

-de

nts (

23 ±

3 ye

ars)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Com

bine

d m

ono-

phas

ic O

CP

with

co

nsta

nt o

estro

gen

and

prog

este

rone

le

vels

(0.0

2–0.

03 m

g et

hiny

lestr

adio

l and

0.

150 

mg

des-

oges

trel o

r 0.0

75 m

g ge

stode

ne)

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

lasti

ng

25–3

1 da

ys in

leng

th,

who

had

not

use

d an

y O

CP

for a

t lea

st 4 

mon

ths b

efor

e en

terin

g th

e stu

dy,

teste

d du

ring

the

LF

and

ML,

ver

ified

by

seru

m o

estro

gen

and

prog

este

rone

leve

ls

Peak

vel

ocity

(rpm

)—E,

pea

k fo

rce

(kg)

—S

and

peak

pow

er

(W)—

E, m

easu

red

durin

g a

forc

e ve

loc-

ity te

st an

d ju

mp

heig

ht (c

m) m

easu

red

usin

g m

ulti

and

squa

t ju

mp

tests

—S

Mod

erat

e

1794 K. J. Elliott-Sale et al.

Tabl

e 2

(con

tinue

d)

Stud

yA

imPa

rtici

pant

hea

lth a

nd

train

ing

stat

usSt

udy

desi

gnO

ral c

ontra

cept

ive

pill

type

Eum

enor

rhei

c gr

oup

desc

riptio

nEx

erci

se o

utco

mes

Qua

lity

ratin

g

Gor

don

et a

l. [4

4]To

mea

sure

the

effec

t of

OC

P an

d M

C o

n pe

ak is

okin

etic

torq

ue

Hea

lthy,

wel

l-tra

ined

w

omen

(20.

6 ± 1.

2 ye

ars)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Mon

opha

sic

OC

PW

omen

with

a se

lf-re

porte

d na

tura

l m

onth

ly M

C (m

ean

cycl

e le

ngth

of

28 d

ays)

teste

d du

ring

the

EF, L

F,

ML

and

LL p

hase

s, ve

rified

by

saliv

ary

oestr

ogen

and

pro

-ge

stero

ne le

vels

Peak

con

cent

ric k

nee

flexo

r and

ext

enso

r to

rque

at 6

0, 1

20, 1

8-

and

240°

(N m

)—S

Very

low

Gor

don

et a

l. [4

5]To

mea

sure

the

effec

t of O

CP

and

eum

enor

rhei

c M

C o

n in

cide

nce

of ̇ V

O2 m

ax

plat

eau

and

asso

ci-

ated

car

dior

espi

rato

ry

dyna

mic

s

Hea

lthy,

phy

sica

lly

activ

e w

omen

(2

1 ± 1.

8 ye

ars)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Mon

opha

sic

OC

P co

n-ta

inin

g 30

 µg

ethi

nyl

oestr

adio

l and

150

 µg

levo

norg

estre

l

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

teste

d du

ring

the

EF, L

F,

ML

and

LL, v

erifi

ed

by M

C h

istor

y an

d sa

livar

y oe

strog

en

and

prog

este

rone

le

vels

Peak

̇ VO

2 (L·

min

−1 )

an

d po

wer

(W)

mea

sure

d du

ring

an

incr

emen

tal r

un to

vo

litio

nal f

atig

ue—

E

Mod

erat

e

Gru

cza

et a

l. [4

6]To

mea

sure

the

effec

t of O

CP

and

eum

enor

rhei

c M

C o

n th

erm

osen

sitiv

ity

Hea

lthy

wom

en

(21.

3 ± 1.

8 ye

ars)

w

ho w

ere

unde

rtak-

ing

appr

oxim

atel

y 2–

3 h

of v

ario

us

activ

ity ty

pes p

er

wee

k

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Mon

opha

sic

OC

P (T

rikvi

lar o

r Neo

-G

entro

l 150

/30)

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

for

one

year

pre

ced-

ing

the

expe

rimen

t an

d w

ho h

ad n

ever

ta

ken

OC

Ps, t

este

d du

ring

the

LF a

nd

ML

phas

e, v

erifi

ed

by B

BT

̇ VO

2 pea

k (m

l·kg·

min

−1)

m

easu

red

durin

g an

in

crem

enta

l cyc

le to

vo

litio

nal f

atig

ue—

E

Low

Gru

cza

et a

l. [4

7]To

mea

sure

the

effec

t of O

CP

and

eum

enor

rhei

c M

C

on c

ardi

ores

pira

tory

re

spon

ses t

o ex

erci

se

Hea

lthy

univ

ersi

ty

stude

nts (

21.3

± 1.

8 ye

ars)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Mon

opha

sic

OC

P (T

rikvi

lar o

r Neo

-G

entro

l)

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

for

1 ye

ar p

rece

ding

th

e ex

perim

ent a

nd

who

had

nev

er ta

ken

OC

Ps, t

este

d du

r-in

g th

e LF

and

ML

phas

e, v

erifi

ed b

y B

BT

̇ VO

2 pea

k (m

l·kg·

min

−1 )

m

easu

red

durin

g an

in

crem

enta

l cyc

le to

vo

litio

nal f

atig

ue—

E

Low

1795Oral Contraceptives and Exercise Performance

Tabl

e 2

(con

tinue

d)

Stud

yA

imPa

rtici

pant

hea

lth a

nd

train

ing

stat

usSt

udy

desi

gnO

ral c

ontra

cept

ive

pill

type

Eum

enor

rhei

c gr

oup

desc

riptio

nEx

erci

se o

utco

mes

Qua

lity

ratin

g

Hic

ks e

t al.

[48]

To m

easu

re th

e eff

ect

of O

CP

and

eum

enor

-rh

eic

MC

on

exer

cise

in

duce

d m

uscl

e da

mag

e, a

nd te

ndon

pr

oper

ties

Hea

lthy,

recr

eatio

n-al

ly a

ctiv

e w

omen

(2

2.3 ±

2.3

year

s)

Para

llel g

roup

, int

er-

vent

ion,

repe

ated

m

easu

res

Com

bine

d m

onop

hasi

c O

CP

with

eth

inyl

oe

strad

iol d

osag

e be

twee

n 20

and

30

 µg

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

(ave

r-ag

e cy

cle

leng

th o

f 28

 day

s) a

nd w

ho

had

neve

r tak

en th

e O

CP,

teste

d du

ring

the

ovul

ator

y ph

ase,

ve

rified

by

seru

m

oestr

ogen

Peak

vol

unta

ry is

omet

-ric

torq

ue (N

 m)—

SM

oder

ate

Isac

co e

t al.

[49]

To m

easu

re th

e eff

ect o

f OC

P an

d eu

men

orrh

eic

MC

on

lipi

d ox

idat

ion

and

card

iore

spira

tory

pa

ram

eter

s at t

he

anae

robi

c th

resh

-ol

d an

d m

axim

um

capa

city

Wei

ght s

tabl

e, h

ealth

y w

omen

(22 ±

2.9

year

s) w

ho w

ere

recr

eatio

nally

act

ive

(defi

ned

as th

ose

not

invo

lved

in a

ny re

gu-

lar e

xerc

ise

train

ing)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Low

-dos

e m

onop

hasi

c O

CP

cont

aine

d 20

( n =

8) o

r 30

( n =

3)

µg o

f eth

inyl

estra

diol

an

d ge

stode

ne o

r le

vono

rges

trel

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

(ave

r-ag

e cy

cle

leng

th o

f 28

 day

s for

at l

east

1 ye

ar) a

nd h

ad n

ot

take

n an

y O

CP

for

mor

e th

an 1

 yea

r pr

ior t

o th

e stu

dy

begi

nnin

g, te

sted

durin

g th

e M

L ph

ase,

ve

rified

by

coun

ting

of d

ays a

nd se

rum

oe

strog

en a

nd p

ro-

geste

rone

leve

ls

̇ VO

2 pea

k (m

l·kg·

min

−1 )

m

easu

red

durin

g an

in

crem

enta

l cyc

le to

vo

litio

nal f

atig

ue—

E

Mod

erat

e

Joyc

e et

 al.

[13]

To m

easu

re th

e eff

ect

of lo

ng-te

rm O

CP

use

on e

ndur

ance

pe

rform

ance

Hea

lthy

wom

en

(21 ±

2.7

year

s) w

ho

wer

e re

crea

tiona

lly

activ

e (d

efine

d as

ex

erci

sing

> 3 

days

pe

r wee

k fo

r at l

east

30 m

in p

er se

ssio

n)

Para

llel g

roup

, ob

serv

atio

nal,

sing

le

mea

sure

Com

bine

d m

onop

hasi

c O

CP

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

lasti

ng

betw

een

28 a

nd

30 d

ays f

or a

t lea

st 12

 mon

ths b

efor

e th

e stu

dy, t

este

d du

ring

the

EF p

hase

, ver

ified

by

seru

m o

estro

gen

and

prog

este

rone

le

vels

Peak

̇ VO

2 (L·

min

−1 )

an

d po

wer

(W)

mea

sure

d du

ring

an in

crem

enta

l cy

cle

to v

oliti

onal

fa

tigue

—E,

and

tim

e to

exh

austi

on (s

) on

a su

bmax

imal

cyc

ling

test—

E

Mod

erat

e

1796 K. J. Elliott-Sale et al.

Tabl

e 2

(con

tinue

d)

Stud

yA

imPa

rtici

pant

hea

lth a

nd

train

ing

stat

usSt

udy

desi

gnO

ral c

ontra

cept

ive

pill

type

Eum

enor

rhei

c gr

oup

desc

riptio

nEx

erci

se o

utco

mes

Qua

lity

ratin

g

Joyc

e et

 al.

[50]

To m

easu

re th

e eff

ect

of se

x an

d O

CP

on

subm

axim

al c

yclin

g pe

rform

ance

fol-

low

ing

an e

ccen

tric

exer

cise

pro

toco

l

Hea

lthy

wom

en

(20.

8 ± 2.

4 ye

ars)

w

ho w

ere

regu

larly

ph

ysic

ally

act

ive,

bu

t not

par

ticip

at-

ing

in a

ny re

gula

r re

sist

ance

-exe

rcis

e tra

inin

g

Para

llel g

roup

, int

er-

vent

ion,

repe

ated

m

easu

res

Com

bine

d m

onop

hasi

c O

CP

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

lasti

ng

betw

een

28 a

nd

30 d

ays f

or a

t lea

st 12

 mon

ths b

efor

e th

e stu

dy, t

este

d du

ring

the

EF p

hase

and

ve

rified

seru

m o

es-

troge

n an

d pr

oges

ter-

one

leve

ls

Peak

̇ VO

2 (m

l·kg·

min

−1 )

and

po

wer

(W) m

easu

red

durin

g an

incr

emen

-ta

l cyc

le to

vol

ition

al

fatig

ue—

E, a

nd m

ean

torq

ue (N

 m·k

g−1 )

an

d to

rque

dec

line

(N m

) mea

sure

d ac

ross

240

max

imal

ec

cent

ric q

uadr

icep

s co

ntra

ctio

ns—

S

Low

Lebr

un e

t al.

[23]

To m

easu

re th

e eff

ect

of O

CP

and

eum

enor

-rh

eic

MC

on

exer

cise

pe

rform

ance

in

high

ly a

ctiv

e w

omen

Hea

lthy,

ath

letic

w

omen

(18–

40

year

s), b

ut n

one

that

co

mpe

ted

in a

erob

ic

activ

ities

(cyc

ling,

tri

athl

on, r

owin

g,

cros

s-co

untry

skiin

g)

Ran

dom

ised

con

trolle

d tri

alTr

ipha

sic

OC

P (S

yn-

phas

ic, 0

.035

 mg

ethi

nyle

strad

iol a

nd

0.5–

1.0 

mg

nore

thin

-dr

one)

Wom

en w

ith a

se

lf-re

porte

d na

tura

l mon

thly

M

C (2

4–35

 day

s in

leng

th) a

nd n

o O

CP

use

in th

e 3 

mon

ths

befo

re e

nter

ing

the

study

, tes

ted

durin

g th

e EF

and

ML

phas

es, v

erifi

ed b

y se

rum

oes

troge

n an

d pr

oges

tero

ne le

vels

̇ VO

2 pea

k (L

·min

−1 )

m

easu

red

durin

g an

in

crem

enta

l cyc

le to

vo

litio

nal f

atig

ue—

E,

time

to e

xhau

stion

(s

) in

a su

bmax

imal

en

dura

nce

test—

E,

time

to e

xhau

stion

(s

) in

an a

naer

obic

sp

eed

test—

E an

d pe

ak q

uadr

icep

s and

ha

mstr

ing

torq

ue

(N m

)—S

Mod

erat

e

Lee

et a

l. [5

1]To

mea

sure

the

effec

t of

OC

P an

d eu

men

or-

rhei

c M

C o

n an

terio

r cr

ucia

te li

gam

ent

elas

ticity

, for

ce to

flex

th

e kn

ee a

nd k

nee

flexi

on–e

xten

sion

hy

stere

sis

Hea

lthy,

non

-ath

letic

w

omen

(24.

7 ± 2

year

s)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Low

dos

e O

CP

cont

aini

ng <

50 µ

g et

hiny

l-estr

adio

l

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

for a

t le

ast 6

 mon

ths,

with

an

aver

age

cycl

e le

ngth

of 2

9 da

ys,

teste

d du

ring

the

EF,

LF, o

vula

tory

and

M

L ph

ases

, ver

ified

by

seru

m o

estro

gen

and

prog

este

rone

le

vels

Kne

e fle

xion

forc

e (N

)—S

Mod

erat

e

1797Oral Contraceptives and Exercise Performance

Tabl

e 2

(con

tinue

d)

Stud

yA

imPa

rtici

pant

hea

lth a

nd

train

ing

stat

usSt

udy

desi

gnO

ral c

ontra

cept

ive

pill

type

Eum

enor

rhei

c gr

oup

desc

riptio

nEx

erci

se o

utco

mes

Qua

lity

ratin

g

Lync

h an

d N

imm

o [5

2]To

mea

sure

the

effec

t of O

CP

and

eum

enor

rhei

c M

C o

n in

term

itten

t exe

rcis

e pe

rform

ance

Hea

lthy

wom

en

(25.

3 ± 6

year

s) w

ho

wer

e re

crea

tiona

lly

activ

e bu

t not

trai

ning

fo

r any

one

spor

t ex

clus

ivel

y

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Low

-dos

e m

onop

hasi

c O

CP

(Fem

oden

e,

Cile

st, O

vran

ette

, M

icro

gyno

n)

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

ovu

lato

ry

MC

s with

an

aver

-ag

e cy

cle

leng

th o

f 29

 day

s, an

d w

ho h

ad

eith

er n

ever

take

n O

CPs

or h

ad n

ot

take

n an

OC

P in

the

last

4 m

onth

s, te

sted

durin

g th

e LF

and

LL

phas

es, v

erifi

ed b

y se

rum

pro

geste

rone

le

vels

̇ VO

2 pea

k (m

l·kg·

min

−1 )

m

easu

red

durin

g an

in

crem

enta

l run

to

volit

iona

l fat

igue

—E,

and

tim

e to

ex

haus

tion

(s) i

n an

in

term

itten

t spr

int

test—

E

Mod

erat

e/ lo

w

Lync

h et

 al.

[53]

To m

easu

re th

e eff

ect

of O

CP

on p

erfo

r-m

ance

and

met

abol

ic

resp

onse

s to,

inte

r-m

itten

t exe

rcis

e du

r-in

g th

e 1s

t or 3

rd w

eek

of th

e O

CP

cycl

e

Hea

lthy,

unt

rain

ed

wom

en (2

3.1 ±

4 ye

ars)

Sing

le g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Low

dos

e m

onop

hasi

c O

CP

(Ovr

anet

te,

Fem

oden

e, M

er-

cilo

n, M

icro

gyno

n,

Bre

vino

r)

N/A

Tim

e to

exh

austi

on (s

) in

the

final

sprin

t of

an in

term

itten

t spr

int

prot

ocol

—E

Mod

erat

e

Mac

kay

et a

l. [6

7]To

mea

sure

the

effec

t of

OC

P us

e on

indi

-re

ct m

arke

rs o

f mus

-cl

e da

mag

e fo

llow

ing

ecce

ntric

cyc

ling

in

wom

en

Hea

lthy

wom

en

(27.

7 ± 4.

5 ye

ars)

w

ho w

ere

not a

ctiv

ely

parti

cipa

ting

in a

ny

resi

stan

ce o

r flex

-ib

ility

trai

ning

in th

e 6 

mon

ths p

rior t

o th

e stu

dy

Para

llel g

roup

, acu

te

inte

rven

tion,

sing

le

mea

sure

Third

and

four

th

gene

ratio

n m

ono-

phas

ic O

CP

(eth

inyl

es

tradi

ol 0

.02 

µg;

dros

pire

none

3 µ

g)

Wom

en w

ith a

se

lf-re

porte

d na

tura

l mon

thly

MC

(b

etw

een

24 a

nd

35 d

ays)

and

who

w

ere

not u

sing

any

fo

rm o

f hor

mon

e-ba

sed

cont

race

ptiv

e m

etho

ds fo

r 6 m

onth

s pr

ior t

o th

e stu

dy,

teste

d du

ring

the

ovu-

lato

ry p

hase

, ver

ified

by

urin

ary

ovul

atio

n de

tect

ion

kit a

nd sa

li-va

ry o

estro

gen

and

prog

este

rone

leve

ls

̇ VO

2 pea

k (m

l·kg·

min

−1 )

mea

s-ur

ed d

urin

g an

incr

e-m

enta

l cyc

ling

test

to

volit

iona

l fat

igue

—E,

m

axim

al v

olun

-ta

ry k

nee

exte

nsor

co

ntra

ctio

n at

90%

kn

ee fl

exio

n (N

)—S,

an

d m

ean

pow

er (W

) du

ring

an e

ccen

tric

cycl

ing

test—

E

Hig

h/ m

oder

ate

1798 K. J. Elliott-Sale et al.

Tabl

e 2

(con

tinue

d)

Stud

yA

imPa

rtici

pant

hea

lth a

nd

train

ing

stat

usSt

udy

desi

gnO

ral c

ontra

cept

ive

pill

type

Eum

enor

rhei

c gr

oup

desc

riptio

nEx

erci

se o

utco

mes

Qua

lity

ratin

g

Mat

tu e

t al.

[68]

To m

easu

re m

axim

al

and

subm

axim

al

exer

cise

out

com

es

at d

iffer

ent p

hase

s of

the

men

strua

l and

O

CP

cycl

e

Hea

lthy,

trai

ned,

w

omen

(25.

5 ± 5.

2 ye

ars)

who

per

form

ed

mod

erat

e to

vig

orou

s ph

ysic

al a

ctiv

ity

at le

ast 4

tim

es p

er

wee

k, a

nd fo

r at l

east

30 m

in p

er b

out

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Seco

nd o

r thi

rd g

en-

erat

ion

mon

opha

sic

OC

P co

ntai

ning

be

twee

n 20

and

35 

µg

of e

thin

yl o

estra

diol

an

d 10

0–20

0 µg

of

prog

estin

)

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

(cyc

le

betw

een

21 a

nd

35 d

ays i

n le

ngth

) w

ho w

ere

non

horm

onal

con

trace

p-tiv

e us

ers f

or a

t lea

st 12

 mon

ths p

rior t

o th

e stu

dy, t

este

d du

r-in

g th

e LF

and

ML

phas

es, t

este

d us

ing

urin

ary

ovul

atio

n de

tect

ion

test

̇ VO

2 pea

k (L

·min

−1 o

r m

l·kg·

min

−1 )

dur

ing

an in

crem

enta

l ram

p te

st to

vol

ition

al

fatig

ue—

E, a

nd ti

me

to e

xhau

stion

(s)

durin

g a

cons

tant

lo

ad te

st at

85%

pea

k po

wer

—E

Hig

h

Min

ahan

et a

l. [5

4]To

mea

sure

the

effec

t of

sex

and

OC

P in

the

resp

onse

to m

uscl

e da

mag

e af

ter i

nten

se

ecce

ntric

exe

rcis

e

Hea

lthy

wom

en

(21 ±

2.7

year

s) w

ho

wer

e ha

bitu

ally

act

ive

(prim

arily

mod

erat

e in

tens

ity e

ndur

ance

-ba

sed

activ

ities

), bu

t w

ho w

ere

not u

nder

-ta

king

a re

sist

ance

tra

inin

g pr

ogra

m

Para

llel g

roup

, int

er-

vent

ion,

repe

ated

m

easu

res

Com

bine

d m

onop

hasi

c O

CP

Wom

en w

ith a

self-

repo

rted

natu

ral

mon

thly

MC

that

oc

curr

ed e

very

28

–30 

days

, tes

ted

durin

g th

e EF

pha

se,

verifi

ed b

y se

rum

oe

strog

en le

vels

Peak

and

mea

n is

omet

-ric

torq

ue (N

 m a

nd

N m

·kg−

1 ) a

cros

s 240

ec

cent

ric c

ontra

c-tio

ns—

S

Low

Min

ahan

et a

l. [5

5]To

mea

sure

the

effec

t of O

CP

and

the

eum

enor

rhei

c M

C o

n co

re b

ody

tem

pera

ture

and

skin

bl

ood

flow

at r

est

and

durin

g ex

erci

se

(tem

pera

te a

nd h

ot

envi

ronm

ents

)

Hea

lthy

wom

en

(22 ±

3.4

year

s) w

ho

wer

e re

crea

tiona

lly

activ

e (3

00–5

00 m

in

per w

eek

of m

oder

ate

inte

nsity

exe

rcis

e)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Low

dos

e co

mbi

ned

mon

opha

sic

OC

PW

omen

with

a se

lf-re

porte

d na

tura

l m

onth

ly M

C (e

very

25

–32 

days

) for

m

ore

than

12 

mon

ths

and

who

had

nev

er

take

n an

y fo

rm o

f sy

nthe

tic h

orm

ones

, te

sted

durin

g th

e EF

ph

ase,

ver

ified

by

seru

m o

estro

gen

and

prog

este

rone

leve

ls

Peak

̇ VO

2 (m

l·kg·

min

−1 )

and

po

wer

(W) m

easu

red

durin

g an

incr

emen

-ta

l cyc

le to

vol

ition

al

fatig

ue—

E, a

nd

mea

n po

wer

out

put

(W) d

urin

g a

3-st

age

subm

axim

al te

st—E

Mod

erat

e

Orte

ga-S

anto

s et a

l. [5

6]To

mea

sure

the

effec

t of O

CP

and

eum

enor

rhei

c M

C o

n su

bstra

te o

xida

tion

durin

g ste

ady-

stat

e ex

erci

se

Hea

lthy

train

ed w

omen

(3

5.6 ±

4.2

year

s)

who

wer

e tra

inin

g in

ei

ther

end

uran

ce o

r str

engt

h ac

tiviti

es fo

r 5–

12 h

per

wee

k

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Stab

le m

onop

hasi

cW

omen

with

a se

lf-re

porte

d na

tura

l m

onth

ly M

C te

sted

durin

g th

e EF

, LF

and

ML

phas

e, v

eri-

fied

by M

C h

istor

y an

d se

rum

oes

troge

n an

d pr

oges

tero

ne

̇ VO

2 pea

k (m

l·kg·

min

−1 )

m

easu

red

durin

g an

in

crem

enta

l run

to

volit

iona

l fat

igue

—E

Low

1799Oral Contraceptives and Exercise Performance

Tabl

e 2

(con

tinue

d)

Stud

yA

imPa

rtici

pant

hea

lth a

nd

train

ing

stat

usSt

udy

desi

gnO

ral c

ontra

cept

ive

pill

type

Eum

enor

rhei

c gr

oup

desc

riptio

nEx

erci

se o

utco

mes

Qua

lity

ratin

g

Pete

rs a

nd B

urro

ws

[57]

To m

easu

re th

e eff

ect

of th

e an

drog

enic

ity

of p

roge

stins

in O

CP

on le

g str

engt

h

Uni

vers

ity a

thle

tes

(20.

2 ± 0.

5 ye

ars)

fro

m a

var

iety

of

spor

ts (c

ricke

t, fo

otba

ll, e

ndur

ance

ru

nnin

g an

d sw

im-

min

g)

Para

llel g

roup

, obs

er-

vatio

nal,

repe

ated

m

easu

res

Mon

opha

sic

OC

P co

ntai

ning

30 

µg

ethi

nyle

strad

iol w

ith

120 

µg le

vono

rg-

este

rel o

r 250

 µg

norg

estim

ate

N/A

Peak

leg

exte

nsio

n an

d fle

xion

torq

ue

(N m

)—S

Mod

erat

e

Qui

nn e

t al.

[58]

To m

easu

re th

e eff

ect

of lo

ng-te

rm O

CP

use

on c

ereb

ral

oxyg

enat

ion

durin

g in

crem

enta

l cyc

ling

to e

xhau

stion

Hea

lthy

wom

en (2

1 ± 3

year

s) w

ho w

ere

recr

eatio

nally

-act

ive

(defi

ned

as 1

50–

300 

min

per

wee

k of

m

oder

ate

inte

nsity

ex

erci

se)

Para

llel g

roup

, ob

serv

atio

nal,

sing

le

mea

sure

28-d

ay c

ombi

ned

mon

opha

sic

OC

PW

omen

with

a

self-

repo

rted

natu

ral m

onth

ly

MC

(28–

30 d

ays i

n le

ngth

) and

had

not

ta

ken

any

form

of

horm

onal

con

trace

p-tio

n fo

r 12 

mon

ths

prio

r to

the

study

, te

sted

durin

g th

e EF

ph

ase,

ver

ified

by

seru

m o

estro

gen

and

prog

este

rone

leve

ls

Peak

̇ VO

2 (m

l·kg·

min

−1 )

and

po

wer

(W) d

urin

g an

in

crem

enta

l cyc

le to

vo

litio

nal f

atig

ue—

E

Mod

erat

e

Rebe

l