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THE HEAT SHOCK PROTEIN RESPONSE IN THE SKELETAL MUSCLE
OF UNTRAINED INDIVIDUALS
Shaun Guest
San Diego State University
School of Exercise and Nutritional Sciences
December 1st, 2009
Modified from Noble, 2008
INTRODUCTION
Magnitude of heat shock response to exercise: Individual characteristics
○ Training status○ Age○ Sex
Absolute workload ○ Intensity ○ Duration
Novelty of exercise stress
Noble, 2008
INTRODUCTIONExercise training with trained individuals: Maximum volume workloads induces the largest HSP
changes (Liu, 1999).
Highest levels of HSP with high intensities
(Liu 1999, 2000).
High-intensity resistance exercise and low-intensity
endurance exercise Blunted/abolished stress responses (Nething, 2003).
HSP response due to increased baseline levels of HSPs pre-exercise (Morton, 2009).
PURPOSE
Based on results from acute exercise bouts and training programs, determine whether exercise training in untrained individuals will lead to an attenuated heat shock protein response.
FINDING THE LITERATURE Data base search:
PubMed/Medline (via EBSCO)
Biosis PreviewsSPORTDiscusWeb of ScienceGoogle Scholar
Search topics: Heat shock proteinsHSP72Skeletal Muscle
PEDro Scale.Quality of Evidence Score of 5
(Maher et al, 2003) Inclusion criteria:
Male subjectsAvg Age: 18-35 yrs
Exclusion criteria:Female subjectsAge > 35 yrsMusculoskeletal abnormalityNeurologic disease
Study Subjects Exercise Protocols Results
Khassaf et al. (2000)
PEDro Scale = 6
N = 7
SedentaryMales
21 ± 2 yrs
VO2max
2.40± 0.27L/min
Modality:One-legged Cycle Ergometry Intensity:70%VO2max
Duration:45 mins
Muscle sample:Vastus lateralis
HSP70 content:Day 6 post-ex ~3000%P<0.05
Large variability 24hr and 48hr post-exslow/reduced ∆
Febbraio & Koukoulas (2000)
PEDro Scale = 7
N = 5
Untrained Males
20.6 ± 1 yrs
VO2max
2.55 ± 0.2 L/min
Modality:Cycle ErgometerIntensity:65% VO2max
Duration:186 ± 15 min
Muscle sample:Vastus lateralis
HSP72 mRNA:@ 10 min no
@ Fatigue-40 2.2x P<0.05
@ Fatigue (~186 min) 2.6x P<0.05
Study Subjects Exercise Protocols Results
Febbraio et al. (2002)
PEDro Scale = 6
N = 7
Physically active males
Modality:Two-legged knee extensor exerciseIntensity:40% Wmax
Duration:4-5 hrs
Muscle Sample:Vastus lateralis
Glycogen DepletedHSP72 mRNA:Post-ex 2x P<0.05HSP72 content:Post-ex 2x P<0.05
Control LegNo sig. ∆s
Fischer et al. (2006)
PEDro Scale = 8
N = 21
Physically active males
Control group
24.1± 0.9 yrs
Pmax= 140±6 W
Modality:Two-legged knee extensor exerciseIntensity:60 extensions/min 50% Pmax
Duration:3 hr
Muscle Sample:Vastus lateralis
HSP72 mRNA:2.5x post-ex P<0.05
HSP72 content:No sig. ∆
Increasing trend @ 0, 3, and 6 hr post-ex
Study Subjects Exercise Protocols Results
Paulsen et al.(2007)
PEDro Scale = 7
N = 11
Sedentary to physically active males
28 ± 4 yrs
Modality: Unilateral, maximal, isokinetic eccentric action Intensity:30/secDuration:30 sets x 10 reps40 minMuscle Sample:Vastus lateralis
HSP70 content:30 min post-ex2x P<0.01
24 hrs post-ex203 ± 37% P<0.05
Day 4 post-ex10x P<0.05
Tupling et al. (2007)
PEDro Scale = 7
N = 10
Untrained males
18 ± 0.47 yrs
MVC torque550 ± 36 Nm
Modality:Single-legged isometric knee extensionIntensity:60% MVCDuration:30min, 50% duty cycle: 5 s contract, 5 s relax
Muscle Sample:Vastus lateralis
HSP70 content:Day 1 post-ex 43% P<0.05
Elevated Day 3 post-ex P<0.05
Day 6 post-ex P<0.05
Study Subjects Exercise Protocols
Results
Morton et al. (2006)
PEDro Scale = 6
N = 8
Active, untrained men
24 ± 4 yrs
VO2max
54.9 ± 4 ml/kg/min
Modality:Treadmill runIntensity:69.8 ± 4.8% VO2max
11.7 ± 0.5 km/hrDuration:45 min
Muscle Sample:Vastus lateralis
HSP70 content:48 hr post-ex 179% 7 days post-ex 178%P<0.05
Peak response 48 hr post-ex:210 ± 70% (135-366%) P>0.05
Morton et al. (2008)
PEDro Scale = 5
N = 6 trained males
29 ± 4 yrs
N = 6 untrained males
28 ± 6 yrsVO2max
54.9 ± 4 ml/kg/min
Trained ParticipantsModality:Treadmill runningIntensity:75%VO2max
Duration:45 min
Muscle Sample:Vastus lateralis
Baseline HSP70: No sign. diff. btw trained vs. untrained
HSP70 content:48 hr post-ex 121 ±10%7 days post-ex118 ± 22% P>0.05
Study Subjects Exercise Protocols Results
Morton et al. (2008)
PEDro Scale = 8
N = 5 Recreationally active males
21 ± 2 yrs
VO2max Pretrained: 49.5±0.9 ml/kg/minVO2max
Posttrained: 54.2±1.8 ml/kg/min
2 x 3 day x 6 wk Modality:Continous/interval runningIntensity:Contin 70%VO2max
Int 100%VO2max
Duration:Int 6 x 4 min, 1 min @ 50% VO2max
Contin: 26-32 min
Continuous TrainingHSP72 content:72 hr post-ex38 ± 41%
Interval TrainingHSP72 content:72 hr post-ex23 ± 36%
No significant ∆s
Vissing et al. (2009)
PEDro Scale = 7
N = 14
Untrained males
23.8 ± 2.8 yrs
Bout18wkBout2Modality:Bench-steppingIntensity:60 steps/minW= 443 J/cycleDuration:1 x 30min step up 1 x 30min step downMuscle Sample:Vastus lateralis
Bout 1 eccentric legHSP70 content:7days post-ex 2.4xP<0.05HSP70 mRNA:3hr post-ex 8.9x24hr post-ex 1.8xDay7 post-ex baselineBout1-Bout23hrs post-ex 4.9xAll P<0.05
DISCUSSION
With exercise training:○ Number of physiological adaptations in human
skeletal muscle.Ex: fat oxidation, LA, muscle remodeling
○ The magnitude of the heat shock response is dependent upon: Individual characteristicsExercise TypeFrequencyIntensityDuration
CONCLUSIONS
Based on results from acute exercise bouts and training programs, it remains unclear whether exercise training will lead to an attenuated response in untrained individuals.
HSP response shown to be vary greatly between individuals.
HSP results reflect genetic variability of skeletal muscle to recover, remodel, and/or adapt to exercise specific stress.
FUTURE RESEARCH
Examine of role of HSP induction with performance.
Continue to use non-damaging exercise protocols ‘clean’ results.
Compare HSP response with training program in untrained and trained individuals.
Questions???