A new study suggests combining weight training with a low-calorie diet preserves much needed lean muscle mass that can be lost through aerobic workouts.
The study, by researchers at Wake Forest University in the US, has been published in the journal Obesity.
During the 18-month study (a single-blind, randomised controlled trial) of 249 adults in their 60s who were overweight or obese, it was found that restricting calories plus resistance training in the form of weight-machine workouts resulted in less muscle loss, but significant fat loss, when compared to weight loss plus walking or weight loss alone.
Participants were randomly assigned to one of three groups: a weight-loss-only group, who followed a calorie-restricted diet with no exercise regimen; a weight loss plus cardio (walking) group; and a weight loss plus weight-training group.
Losing weight is generally recommended for those with obesity, but preserving muscle – while losing fat – is particularly important for older adults in order to maximise functional benefit, according to the study’s lead author Kristen Beavers.
‘A lot of older adults will walk as their exercise of choice,’ she said. ‘But this research shows that if you’re worried about losing muscle, weight training can be the better option.’
‘Surprisingly, we found that cardio workouts may actually cause older adults with obesity to lose more lean mass than dieting alone.’
The study also reveals that loss of fat was associated with faster walking speed, while loss of muscle was associated with reduced knee strength.