Lower limb alactic anaerobic power output assessed with different techniques in morbid obesity

Abstract

Short-term alactic anaerobic performance in jumping (5 consecutive jumps with maximal effort), sprint running (8 m) and stair climbing (modified Margaria test) were measured in 75 obese subjects (BMI: 40.3+/-5.0 kg/m2) and in 36 lean control subjects (BMI: 22.4+/-3.2 kg/m2) of the same age and gender distribution. The results show that obese subjects attained a significantly lower specific (per unit body mass) power output both in jumping (W(spec,j); p<0.001) and stair climbing (W(spec,s); p<0.001) and run at a significantly lower average velocity (v; p<0.001) during sprinting. In spite of the different motor skillfulness required to accomplish the jumping and climbing tests, W(spec,s) (and hence the vertical velocity in climbing, v(v)) was closely correlated with W(spec,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 2 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 also entailed a different locomotion pattern with shorter step length (L(s); p<0.001), lower frequency (p<0.001) and longer foot contact time with ground (T(c,r); p<0.001). W(spec,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 v(v) in stair climbing; and III) with T(c,r) (R2=0.492, p<0.001), L(s) (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, largely rely on their effective specific power output to perform complex anaerobic tasks, and they suffer from the disproportionate excess of inert mass of fat. Furthermore, in view of the sedentary style of life and the consequent degree of muscle de-conditioning accompanying this condition, it may prove useful to implement rehabilitation programs for obesity with effective power training protocols.

Effects of a multidisciplinary weight loss intervention on anaerobic and aerobic aptitudes in severely obese adolescents

“…VJHs in our study were lower than those reported in nonobese children and adolescents 24 ; this is in agreement with the previous studies in obese adolescents 27 and adults, 39 and well explained by the discrepancy between the small difference in lower limb muscle masses between normal and obese adolescents on the one hand and the major overload to be brought up by the obese subjects on the other. VJH increased with age and pubertal development in both sexes and were generally higher in boys than in girls.…”

Influence of gender, age and BMI on lower limb muscular power output in a large population of obese men and women

“…W per unit body weight, which represents the actual correlate of the anaerobic performance also in obese subjects, 10 female subjects appear to be at a greater disadvantage for effect of the degree of obesity, the major limitations being suffered by older individuals with higher BMI.…”

“…In spite of the motor limitation experienced by extremely obese subjects, mainly due to the hampering effect of fat excess and the poor physical conditioning, a modified SCT has been shown to be a reliable indicator of available power in lower limb muscles, also in these kind of subjects, 10 and has been widely employed on the clinical ground to evaluate the effectiveness of body weight reduction programmes based on physical activity for the improvement of muscle performance and motor coordination. [11][12][13] In the obese individuals of the present study, maximal voluntary lower limb power output was relatively constant up to a certain age (the peak value being displayed by subjects of both genders in the third decade) and then steadily decreased thereafter at the rate of about 1.5-1.6% per year, as it can be seen in Figure 1.…”

“…Wspec, which has been shown to be a major determinant of everyday life motor performance. 10 In fact, obese women have been reported to experience more serious motor problems than men and in general to consider themselves …”

“…[7][8][9] Nonetheless, it has been demonstrated that obese patients actually display major motor limitations due to a reduction of both aerobic and anaerobic capabilities, which can be evidenced with adequate functional motor tests suitable for this disabled condition. [10][11][12][13] While reductions in aerobic power interfere with the capability to sustain relatively intense and prolonged exercise, anaerobic power is related to the accomplishment of short and vigorous movements more directly involved in everyday life activities (ie rapidly climbing up a flair of stairs or running to catch a bus) or even in brisk postural adjustments to prevent falls and accidental crushes. Unfortunately, these studies, although providing a physiological basis for the quantification of the derangement of motor physical functions, were performed on groups of relatively young patients within a limited range of age and with a major degree of obesity.…”