Secular changes in anaerobic fitness test performance in healthy 6- to 17-year-old Australasians were examined by meta-analysis of 232,564 power- and speed-test performances between 1960 and 2002. Overall, power-test performance improved at a rate of +0.05% [95% confidence interval (CI) = +0.01% to +0.09%] per annum, and speed at +0.04% (CI = +0.02% to +0.06%) per annum. Results indicate that anaerobic-fitness-test performances have remained relatively stable in Australasian children and adolescents in recent decades.
Grant R. Tomkinson, Michael J. Hamlin, and Timothy S. Olds
Michael J. Hamlin, Will G. Hopkins, and Stephen C. Hollings
Lower barometric air pressure at altitude can affect competitive performance of athletes in some sports. Reported here are the effects of various altitudes on elite track-and-field athletes’ performance.
Lifetime track-and-field performances of athletes placed in the top 16 in at least 1 major international competition between 2000 and 2009 were downloaded from the database at tilastopaja.org. There were 132,104 performances of 1889 athletes at 794 venues. Performances were logtransformed and analyzed using a mixed linear model with fixed effects for 6 levels of altitude and random quadratic effects to adjust for athlete age.
Men’s and women’s sprint events (100–400 m) showed marginal improvements of ~0.2% at altitudes of 500–999 m, and above 1500 m all but the 100- and 110-m hurdles showed substantial improvements of 0.3–0.7%. Some middle- and long-distance events (800–10,000 m) showed marginal impairments at altitudes above 150 m, but above 1000 m the impairments increased dramatically to ~2–4% for events >800 m. There was no consistent trend in the effects of altitude on field events up to 1000 m; above 1000 m, hammer throw showed a marginal improvement of ~1% and discus was impaired by 1–2%. Above 1500 m, triple jump and long jump showed marginal improvements of ~1%.
In middle- and long-distance runners, altitudes as low as 150 to 299 m can impair performance. Higher altitudes (≥1000 m) are generally required before decreases in discus performance or enhancements in sprinting, triple and long jump, or hammer throw are seen.
Nuttaset Manimmanakorn, Jenny J. Ross, Apiwan Manimmanakorn, Samuel J.E. Lucas, and Michael J. Hamlin
To compare whole-body vibration (WBV) with traditional recovery protocols after a high-intensity training bout.
In a randomized crossover study, 16 athletes performed 6 × 30-s Wingate sprints before completing either an active recovery (10 min of cycling and stretching) or WBV for 10 min in a series of exercises on a vibration platform. Muscle hemodynamics (assessed via near-infrared spectroscopy) were measured before and during exercise and into the 10-min recovery period. Blood lactate concentration, vertical jump, quadriceps strength, flexibility, rating of perceived exertion (RPE), muscle soreness, and performance during a single 30-s Wingate test were assessed at baseline and 30 and 60 min postexercise. A subset of participants (n = 6) completed a 3rd identical trial (1 wk later) using a passive 10-min recovery period (sitting).
There were no clear effects between the recovery protocols for blood lactate concentration, quadriceps strength, jump height, flexibility, RPE, muscle soreness, or single Wingate performance across all measured recovery time points. However, the WBV recovery protocol substantially increased the tissue-oxygenation index compared with the active (11.2% ± 2.4% [mean ± 95% CI], effect size [ES] = 3.1, and –7.3% ± 4.1%, ES = –2.1 for the 10 min postexercise and postrecovery, respectively) and passive recovery conditions (4.1% ± 2.2%, ES = 1.3, 10 min postexercise only).
Although WBV during recovery increased muscle oxygenation, it had little effect in improving subsequent performance compared with a normal active recovery.