Abstract des Autors

Purpose: To assess whether stepping-based weight bearing exercise (WBE) can elicit peak activation of upper leg muscles similar to resistance exercise (RE) at an intensity required to induce strength gains in elderly women.
Methods: Muscular activation of several upper leg muscles was measured during RE and WBE in a cohort of 19 healthy elderly women (69.3 +/- 3.4 years). WBE consisted of forward and lateral stepping with step heights of 10, 20 and 30 cm. Muscular activation was compared to 60% of one-repetition maximum (1-RM) of congruent RE.
Results: Peak activation during WBE was higher than RE at 60% 1-RM during forward and lateral stepping in vastus lateralis starting at 20 cm (p = 0.049 and p = 0.001), and biceps femoris at 30 cm step height (p = 0.024 and p = 0.030). Gluteus maximus peak activation matched RE at 60% 1-RM at 20 and 30 cm step height regardless of step direction (p >/= 0.077). Peak activation of the rectus femoris and gluteus medius matched RE activation at 60% 1-RM during lateral stepping at 30 cm (p = 0.355 and p = 0.243, respectively) but not during forward stepping. WBE did not induce similar activation as RE in the semitendinosus.
Conclusion: In WBE, most upper leg muscles were recruited at an equal or higher intensity than in RE at 60% 1-RM. Lateral stepping at 30 cm step height showed the highest training potential of all WBE’s applied.