Department of Sport and Exercise Sciences, University of Chichester, College Lane, Chichester, West Sussex, PO19 6PE, UK.
Eur J Appl Physiol. 2012 Nov;112(11):3699-707. doi: 10.1007/s00421-012-2338-4. Epub 2012 Feb 18.
Age-associated decline in muscle mass and strength impairs functional mobility in older adults. We examined the effects of an eccentric endurance exercise programme (downhill treadmill walking, DTW) at a self-selected walking speed (SSWS) on functional mobility and eccentric and concentric strength of m. quadriceps femoris of older adults. Twenty-four older adults (67 ± 4 years) were randomly assigned to complete 3 × 30 min treadmill walks per week for 12 weeks on a level (n = 11, LTW 0%) or downhill (n = 13, DTW -10%) treadmill gradient at SSWS. SSWS was re-adjusted every 4 weeks. Participants were assessed for five repetition sit-to-stand (5-RSTS), maximal walking speed (MWS), timed up-and-go (TUG) and dynamic strength. SSWS was similar for both groups with increases from 1.18 ± 0.11 to 1.53 ± 0.09 m s(-1) (LTW) and 1.26 ± 0.16 to 1.61 ± 0.12 m s(-1) (DTW) (time, P < 0.01). Improvements in 5-RSTS, MWS and TUG were substantial and similar for both groups (time, P < 0.01). 5-RSTS (baseline LTW: 8.50 ± 1.19 s, DTW: 8.54 ± 1.52 s) improved by 32 and 34%. MWS (baseline LTW: 2.39 ± 0.38 m s(-1), DTW: 2.40 ± 0.33 m s(-1)) improved by 22 and 23%. TUG (baseline LTW: 5.58 ± 0.51 s, DTW: 5.46 ± 0.89 s) improved by 22% for both groups. Peak eccentric and concentric torque did not change. Knee angle of concentric peak torque (180° s(-1)) was decreased after 12 weeks in both groups (LTW: 37° ± 16° to 26° ± 14°, DTW: 42° ± 18° to 37° ± 16°, P < 0.05). Regular level and downhill treadmill walking by older adults, at a SSWS, results in substantial improvements in functional mobility. Changes in functional mobility were not explained by changes in dynamic strength of the m. quadriceps femoris.
年龄相关的肌肉质量和力量下降会损害老年人的功能性移动能力。我们研究了在自我选择的步行速度（SSWS）下进行离心耐力运动方案（下坡跑步机行走，DTW）对老年人股四头肌的功能性移动能力以及离心和向心强度的影响。24 名老年人（67±4 岁）被随机分配，每周完成 3 次×30 分钟的跑步机行走，在水平跑步机（n=11，LTW 0%）或下坡跑步机（n=13，DTW-10%）上以 SSWS 进行。每 4 周重新调整 SSWS。参与者接受 5 次重复坐站（5-RSTS）、最大步行速度（MWS）、计时起立行走（TUG）和动态强度测试。两组的 SSWS 相似，均从 1.18±0.11 增加到 1.53±0.09 m/s（LTW）和 1.26±0.16 增加到 1.61±0.12 m/s（DTW）（时间，P<0.01）。两组的 5-RSTS、MWS 和 TUG 均有显著改善（时间，P<0.01）。5-RSTS（基线 LTW：8.50±1.19 s，DTW：8.54±1.52 s）分别提高了 32%和 34%。MWS（基线 LTW：2.39±0.38 m/s，DTW：2.40±0.33 m/s）分别提高了 22%和 23%。TUG（基线 LTW：5.58±0.51 s，DTW：5.46±0.89 s）两组均提高了 22%。峰值离心和向心扭矩没有变化。两组在 12 周后，在 180°/s 时的股四头肌向心峰值扭矩的膝关节角度（180°/s）都降低了（LTW：37°±16°至 26°±14°，DTW：42°±18°至 37°±16°，P<0.05）。老年人在 SSWS 下进行常规水平和下坡跑步机行走，可显著改善功能性移动能力。功能性移动能力的变化不能用股四头肌的动态力量变化来解释。
