Ann Intern Med. 2015 Mar 3;162(5):325-34. doi: 10.7326/M14-1189.
Exercise reduces obesity and related glucose tolerance, but whether increasing exercise intensity offers additional benefit at fixed exercise amounts is unknown.
To determine the separate effects of exercise amount and intensity on abdominal obesity and glucose tolerance.
24-week, single-center, parallel-group trial from 2009 to 2013. (ClinicalTrials.gov: NCT00955071).
Kingston, Ontario, Canada.
300 abdominally obese adults.
Control (no exercise) (n = 75) or 5 weekly sessions of low-amount, low-intensity exercise (LALI) (180 and 300 kcal/session for women and men, respectively, at 50% of maximum oxygen consumption [V̇o2peak]) (n = 73); high-amount, low-intensity exercise (HALI) (360 and 600 kcal/session, respectively, at 50% of V̇o2peak) (n = 76); or high-amount, high-intensity exercise (HAHI) (360 and 600 kcal/session, respectively, at 75% of V̇o2peak) (n = 76). Daily unsupervised physical activity and sedentary time were measured by accelerometer.
Waist circumference and 2-hour glucose level (primary outcomes) and cardiorespiratory fitness and measures of insulin action (secondary measurements).
217 participants (72.3%) completed the intervention. Mean exercise time in minutes per session was 31 (SD, 4.4) for LALI, 58 (SD, 7.6) for HALI, and 40 (SD, 6.2) for HAHI. Daily unsupervised physical activity and sedentary time did not change in any exercise group versus control (P > 0.33). After adjustment for age and sex in a linear mixed model, reductions in waist circumference were greater in the LALI (-3.9 cm [95% CI, -5.6 to -2.3 cm]; P < 0.001), HALI (-4.6 cm [CI, -6.2 to -3.0 cm]; P < 0.001), and HAHI (-4.6 cm [CI, -6.3 to -2.9 cm]; P < 0.001) groups than the control group but did not differ among the exercise groups (P > 0.43). After adjustment for covariates, reductions in 2-hour glucose level were greater in the HAHI group (-0.7 mmol/L [-12.5 mg/dL] [CI, -1.3 to -0.1 mmol/L {-23.5 to -1.5 mg/dL}]; P = 0.027) than the control group but did not differ for the LALI or HALI group versus the control group (P > 0.159). Weight loss was greater in all exercise groups than the control group (P < 0.001); however, reduction in body weight did not differ among the exercise groups (P > 0.182).
The clinical importance of reducing 2-hour glucose level in nondiabetic adults remains undetermined.
Fixed amounts of exercise independent of exercise intensity resulted in similar reductions in abdominal obesity. Reduction in 2-hour glucose level was restricted to high-intensity exercise.
运动可降低肥胖和相关的葡萄糖耐量，但在固定运动量的情况下，增加运动强度是否会带来额外的益处尚不清楚。
确定运动量和强度对腹部肥胖和葡萄糖耐量的单独影响。
2009 年至 2013 年进行的 24 周、单中心、平行组试验。（ClinicalTrials.gov：NCT00955071）。
加拿大安大略省金斯顿。
300 名腹部肥胖成年人。
对照组（无运动）（n = 75）或每周 5 次低量低强度运动（LALI）（女性和男性分别为 180 和 300 千卡/次，分别为最大摄氧量[V̇o2peak]的 50%）（n = 73）；高量低强度运动（HALI）（女性和男性分别为 360 和 600 千卡/次，分别为 V̇o2peak 的 50%）（n = 76）；或高量高强度运动（HAHI）（女性和男性分别为 360 和 600 千卡/次，分别为 V̇o2peak 的 75%）（n = 76）。通过加速度计测量日常非监督性体力活动和久坐时间。
腰围和 2 小时血糖水平（主要结果）以及心肺功能和胰岛素作用的测量（次要测量）。
217 名参与者（72.3%）完成了干预。LALI 每次运动时间为 31 分钟（SD，4.4），HALI 为 58 分钟（SD，7.6），HAHI 为 40 分钟（SD，6.2）。与对照组相比，任何运动组的日常非监督性体力活动和久坐时间均未发生变化（P > 0.33）。在线性混合模型中，根据年龄和性别进行调整后，LALI（-3.9 厘米[95%CI，-5.6 至-2.3 厘米]；P < 0.001）、HALI（-4.6 厘米[CI，-6.2 至-3.0 厘米]；P < 0.001）和 HAHI（-4.6 厘米[CI，-6.3 至-2.9 厘米]；P < 0.001）组的腰围减少量大于对照组，但运动组之间的差异无统计学意义（P > 0.43）。调整协变量后，HAHI 组的 2 小时血糖水平降低量大于对照组（-0.7 mmol/L[-12.5 mg/dL] [CI，-1.3 至-0.1 mmol/L {-23.5 至-1.5 mg/dL}]; P = 0.027），但与 LALI 或 HALI 组相比，对照组的差异无统计学意义（P > 0.159）。与对照组相比，所有运动组的体重减轻量均更大（P < 0.001）；然而，运动组之间的体重减轻量无差异（P > 0.182）。
降低非糖尿病成年人 2 小时血糖水平的临床重要性仍不确定。
固定量的运动而不考虑运动强度会导致腹部肥胖的相似减少。2 小时血糖水平的降低仅限于高强度运动。
