Seasonal Changes in physiological parameters in young club level rowers

Aims: To evaluate variations in biometrics, physiological and performance parameters over a seasonal training – from September to March - in club level young rowers. Methods: Six young rowers, age 13-15, affiliated with a rowing club member of the Italian Rowing Federation, were assessed three times at regular three-months intervals (September, December, and March) during the 2011 season. Biometrics evaluations included stature, body mass and body composition, whereas physiological assessments on rowing ergometer included maximum oxygen uptake (VO2max) obtained during an incremental test, and average power output values obtained during a 2000m trial (W2000) and during a 20-sec (W20) and a 60-sec (W60) maximal effort tests. The time to complete the 2000m trial (t2000) on rowing ergometer was chosen as index of performance. Results: From September to March body mass decreased not significantly while the stature, due to growth for age, increased from 162.2 cm to 165.3 cm (+1.95%, p=0.0006) so that BMI decreased significantly (-5.85%, p=0.008). Body fat mass decreased not significantly from 22.0% to 19.2%. Maximum oxygen uptake decreased from 59.8 ml/Kg/min in September to 54.3 ml/Kg/min in December (-9.2%, p=0.015), before rising to 66.6 ml/Kg/min in March (+22.8%, p=0.002). Average power over 20-sec and 60-sec increased respectively from 300 to 366 W (+21.7%, p=0.009), and from 309 to 353 W (+14.2%, p=0.045). The time to complete 2000m on rowing ergometer decreased from 8’08” in September to 7’36” in March (-6.6%, p=0.0001). Conclusions: Seasonal variation in body mass and body composition was minimal, while body height, an important but not trainable factor in rowing performance, increased due to the growth. The main physiological factor correlated with rowing ergometer performance (VO2max) increased, although in a variable manner. The indices of anaerobic power (W20 and W60) continuously increased from the initial phase of training to workout. The current findings suggest that seasonal training in club level young rowers was effective in increasing maximal oxygen uptake and muscle power output, correlated with performance on 2000m rowing ergometer.