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1.  Fatigue is not a necessary stimulus for strength gains during resistance training 
Background: High resistance training enhances muscular strength, and recent work has suggested an important role for metabolite accumulation in this process.
Objective: To investigate the role of fatigue and metabolite accumulation in strength gains by comparing highly fatiguing and non-fatiguing isotonic training protocols.
Methods: Twenty three healthy adults (18–29 years of age; eight women) were assigned to either a high fatigue protocol (HF: four sets of 10 repetitions with 30 seconds rest between sets) to maximise metabolic stress or a low fatigue protocol (LF: 40 repetitions with 30 seconds between each repetition) to minimise changes. Subjects lifted on average 73% of their 1 repetition maximum through the full range of knee extension with both legs, three times a week. Quadriceps isometric strength of each leg was measured at a knee joint angle of 1.57 rad (90°), and a Cybex 340 isokinetic dynamometer was used to measure the angle-torque and torque-velocity relations of the non-dominant leg.
Results: At the mid-point of the training, the HF group had 50% greater gains in isometric strength, although this was not significant (4.5 weeks: HF, 13.3 (4.4)%; LF, 8.9 (3.6)%). This rate of increase was not sustained by the HF group, and after nine weeks of training all the strength measurements showed similar improvements for both groups (isometric strength: HF, 18.2 (3.9)%; LF, 14.5 (4.0)%). The strength gains were limited to the longer muscle lengths despite training over the full range of movement.
Conclusions: Fatigue and metabolite accumulation do not appear to be critical stimuli for strength gain, and resistance training can be effective without the severe discomfort and acute physical effort associated with fatiguing contractions.
doi:10.1136/bjsm.36.5.370
PMCID: PMC1724546  PMID: 12351337
2.  Effect of stretching duration on active and passive range of motion in the lower extremity 
OBJECTIVES: To investigate the effect of different durations of stretching (five or 15 seconds) on active and passive range of motion (ROM) in the lower extremity during a five week flexibility training programme. METHOD: Twenty four university sport club members (19 men, five women), with a mean (SD) age of 20.5 (1.35) years, were randomly assigned to one of three groups (two treatment and one control). The two treatment groups participated in a static active stretching programme three times a week for a five week period, holding each stretch for a duration of either five or 15 seconds. The total amount of time spent in a stretched position was controlled. The five second group performed each stretch nine times and the 15 second group three times resulting in a total stretching time of 45 seconds for both groups for each exercise. The control group did not stretch. Active and passive ROM were determined during left hip flexion, left knee flexion, and left knee extension before and after the training programme using an inclinometer. RESULTS: Two factor within subject analysis of variance indicated no significant difference in ROM before and after the training programme for the control group. However, significant improvements in active and passive ROM (p < 0.05) were shown in both treatment groups after the five week training programme. Two factor analysis of variance with repeated measures and post hoc analysis showed significant differences between the treatment groups and the control group for the improvements observed in active (p < 0.05) and passive (p < 0.05) ROM. The five and 15 second treatment groups did not differ from one another when ROM was assessed passively, but significant differences were apparent for active ROM, with the 15 second group showing significantly greater improvements (p < 0.05) than the five second group. CONCLUSION: These findings suggest that holding stretches for 15 seconds, as opposed to five seconds, may result in greater improvements in active ROM. However, sustaining a stretch may not significantly affect the improvements gained in passive ROM. 



PMCID: PMC1756178  PMID: 10450481
3.  Virus infections and sports performance--a prospective study. 
There are numerous anecdotal reports relating infection to deterioration in sporting performance. Unexplained failures by top sportsmen are often attributed to recent or current infections. We have carried out a prospective investigation to determine the effect of viral infections on the performance of a group of 68 elite track and field athletes. Athletes were monitored for evidence of viral infection during winter training and their form was assessed subjectively and also semi-objectively by analogue scale questionnaires. Static elevated titres of neutralising antibody to Coxsackie B 1-5 were present in 54% of the athletes and 79% had serological evidence of past viral infection. The raised titres did not relate to poor performance. There was no evidence that loss of form was related to subclinical infection. Elevated antibody levels to Coxsackie B and other common viruses should be interpreted with great caution when assessing athletes complaining of poor performance.
PMCID: PMC1478736  PMID: 2852528

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