Short-term alactic anaerobic performance in jumping (5 consecutive jumps with maximal effort), sprint running (8 m) and stair climbing (modified Margaria test) has been measured in 75 obese subjects (body mass index, BMI: 40.3 ± 5.0 kg m-2) and in 36 lean control subjects (BMI: 22.4 ± 3.2 kg m-2) of the same age and gender distribution. The results showed that obese subjects attained a significantly lower specific (per unit body mass) power output both in jumping ( Wspec,j; p < 0.001) and stair climbing ( Wspec,s; p < 0.001) and run at a significantly lower average velocity (v; p < 0.001) during sprinting. In spite of the different motor skilfulness required to accomplish the jumping and climbing tests, Wspec,s (and hence the vertical velocity in climbing, vv) was closely correlated with Wspec,j (R2 = 0.427, p < 0.001). In jumping, although the average force during the positive work phase was significantly higher in obese subjects (p < 0.001), no difference between the two groups was detected in absolute power. In stair climbing the absolute power output of obese resulted significantly higher (18%) than that of lean controls (p < 0.001). In sprint running, the lower average horizontal velocity attained by obese subjects entailed also a different locomotion pattern with shorter step length (Ls; p < 0.001), lower frequency (p < 0.001) and longer foot contact time with ground (Tc,r; p < 0.001). Wspec,j seems to be a determinant of the poorer motor performance of obese, being significantly correlated with: i) the vertical displacement of the centre of gravity (R2 = 0.853, p < 0.001) in jumping; ii) with vv in stair climbing and, iii) with Tc,r (R2 = 0.492, p < 0.001), Ls (R2 = 0.266, p < 0.001) and v (R2 = 0.454, p < 0.001) in sprinting. The results suggest that obese individuals, although partially hampered in kinetic movements, rely largely on their effective specific power output to perform complex anaerobic tasks, and they suffer from the disproportionate excess of the inert mass of fat. In view also of the sedentary style of life and the consequent degree of muscle deconditioning accompanying this condition, it may prove useful to implement rehabilitation programmes for obesity with effective power training protocols.
Lower limb alactic anaerobic power output assessed with different techniques in morbid obesity
Lafortuna CL;
2002
Abstract
Short-term alactic anaerobic performance in jumping (5 consecutive jumps with maximal effort), sprint running (8 m) and stair climbing (modified Margaria test) has been measured in 75 obese subjects (body mass index, BMI: 40.3 ± 5.0 kg m-2) and in 36 lean control subjects (BMI: 22.4 ± 3.2 kg m-2) of the same age and gender distribution. The results showed that obese subjects attained a significantly lower specific (per unit body mass) power output both in jumping ( Wspec,j; p < 0.001) and stair climbing ( Wspec,s; p < 0.001) and run at a significantly lower average velocity (v; p < 0.001) during sprinting. In spite of the different motor skilfulness required to accomplish the jumping and climbing tests, Wspec,s (and hence the vertical velocity in climbing, vv) was closely correlated with Wspec,j (R2 = 0.427, p < 0.001). In jumping, although the average force during the positive work phase was significantly higher in obese subjects (p < 0.001), no difference between the two groups was detected in absolute power. In stair climbing the absolute power output of obese resulted significantly higher (18%) than that of lean controls (p < 0.001). In sprint running, the lower average horizontal velocity attained by obese subjects entailed also a different locomotion pattern with shorter step length (Ls; p < 0.001), lower frequency (p < 0.001) and longer foot contact time with ground (Tc,r; p < 0.001). Wspec,j seems to be a determinant of the poorer motor performance of obese, being significantly correlated with: i) the vertical displacement of the centre of gravity (R2 = 0.853, p < 0.001) in jumping; ii) with vv in stair climbing and, iii) with Tc,r (R2 = 0.492, p < 0.001), Ls (R2 = 0.266, p < 0.001) and v (R2 = 0.454, p < 0.001) in sprinting. The results suggest that obese individuals, although partially hampered in kinetic movements, rely largely on their effective specific power output to perform complex anaerobic tasks, and they suffer from the disproportionate excess of the inert mass of fat. In view also of the sedentary style of life and the consequent degree of muscle deconditioning accompanying this condition, it may prove useful to implement rehabilitation programmes for obesity with effective power training protocols.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
