高强度间歇训练帮老年人保住肌肉
As we get older, losing weight can be a double-edged sword: along with the fat, we often lose valuable muscle. Now a study from Australia suggests that the type of exercise you choose can make a real difference.
Researchers at the University of the Sunshine Coast recruited 123 healthy adults with an average age of 72. The volunteers were divided into three groups and spent six months doing supervised gym sessions three times a week. One group did high-intensity interval training, known as HIIT, which involves short bursts of hard effort followed by rest. A second group did moderate exercise, and a third group did gentle, low-intensity workouts.
All three groups lost a modest amount of body fat. But there was one important difference. People in the moderate group also lost a small amount of lean muscle, while those doing HIIT held on to theirs.
The researchers believe this is because intense exercise puts more stress on the muscles, which signals the body to keep them. Muscle is vital for strength, balance and independence in later life.
The team cautioned that the differences were small, and other recent studies have produced mixed results. Still, they say the findings show that healthy ageing is about more than the number on the scales.
上了年纪以后，减肥往往是把双刃剑：脂肪掉了，宝贵的肌肉也跟着流失。澳大利亚的一项新研究发现，选什么样的运动，结果可能大不一样。
阳光海岸大学的研究人员招募了 123 名健康的老年人，平均年龄 72 岁。志愿者分成三组，在专人指导下每周去健身房锻炼三次，坚持了六个月。第一组做高强度间歇训练（HIIT），也就是短时间全力运动、再休息，交替进行；第二组做中等强度运动；第三组做轻松的低强度运动。
三组人都减掉了一些脂肪，但有一个关键区别：中等强度组的人同时掉了少量肌肉，而做 HIIT 的人肌肉没有减少。
研究人员认为，这是因为高强度运动对肌肉的刺激更大，身体因此会把肌肉留住。对老年人来说，肌肉关系到力气、平衡，以及能不能独立生活。
研究团队也提醒，各组之间的差别并不大，近期其他研究的结论也不尽相同。不过他们表示，这些结果说明，健康地变老，看的不只是体重秤上的数字。