Twice-weekly exercise helped grip strength in older Vietnamese adults with muscle loss

From middle age on, people slowly lose muscle. When the loss goes far enough that both muscle mass and strength are low, doctors call it sarcopenia. It makes walking, climbing stairs and getting up from a chair harder, and it is linked to falls, fractures and hospital stays. Strength training is the best-studied way to fight it, and eating enough protein is thought to help muscles respond to that training. How much the food part adds on top of exercise is still debated.

Most trials have been done in clinics in wealthy countries. A team from the University of Medicine and Pharmacy at Ho Chi Minh City wanted to know what a simple program could do in ordinary communities in Vietnam, among people found through screening rather than at a doctor’s office.

What they did

Earlier, the team had screened 660 older adults in three communities of Can Gio, a coastal district of Ho Chi Minh City. Of these, 280 (about 42%) met Asian diagnostic criteria for sarcopenia or severe sarcopenia. For the trial they randomly picked 30 people aged 60 to 70 from each community who could walk on their own, 90 in total.

This was a cluster-randomized trial: whole communities, not individuals, were assigned by lot to a program.

• Control: one group session of health education about food and exercise, with a handbook and videos. Everyone got this.
• Exercise: the same education plus two one-hour sessions a week for 24 weeks, half music-based aerobic exercise and half strength training for the major muscle groups. For the first 12 weeks, one session a week was supervised and the other done at home with videos; after that, supervision dropped to once a month.
• Exercise plus nutrition: the same exercise program, plus weekly personal nutrition counselling and a daily supplement drink with about 270 kcal and 11 g of protein, both for the first 12 weeks only.

At the start, after 12 weeks and after 24 weeks, staff who were not told which program a community had measured muscle mass (with a scale that sends a weak current through the body), grip strength and the speed of a 6-metre walk.

What they found

• Grip strength. After 24 weeks, grip strength had fallen by about 1.1 kg in the control community and risen by about 1.3 kg with exercise and 1.1 kg with exercise plus nutrition. Compared with control, that is roughly 2.5 kg and 2.2 kg better. The gains were larger at 12 weeks, while supervision was still weekly.
• Walking speed. Both active groups walked faster after 12 weeks. By 24 weeks the exercise-only community was still about 0.2 m/s faster than control; the exercise-plus-nutrition community’s gain had shrunk and was no longer clearly different from control.
• Muscle mass. Changes were small. The exercise-only community gained slightly more than control (0.12 kg/m² on the muscle index); the exercise-plus-nutrition community did not differ from control.
• Nutrition added nothing clear. The two active groups did not differ in grip strength, and on walking speed and muscle mass the exercise-only community did better.

What to keep in mind

• One community per group. This is the authors’ main caveat. Because each program ran in just one community, any difference between communities (in who lives there, or how the program was run) is mixed up with the effect of the program. They call the comparisons “exploratory” and say they should not be read as definitive treatment effects.
• The groups started out different. The control community had more men (47% versus 17% and 20%) and walked more slowly at the start.
• Too small for modest effects. The study size was planned for a large effect and did not allow for the cluster design.
• Missing data. Attendance, how much of the supplement people drank, changes in diet and side effects were not analysed. The trial was registered only after it had been done.
• Nutrition isn’t ruled out. The nutrition support lasted only 12 weeks, there was no nutrition-only group, and the authors stress the results are not evidence that nutrition doesn’t matter.
• Limited reach. All participants were 60 to 70, could walk unaided and lived in one district.

Why it matters

Sarcopenia is common: in this district, more than four in ten screened older adults had it. The trial suggests that a cheap program built on twice-weekly exercise, mostly done at home with videos, can improve strength and walking in people found through community screening, while those who got advice alone slowly lost strength. The fading of the gains once supervision was reduced hints that keeping people training matters. Whether the nutrition part adds anything needs larger trials with several communities per group, which the authors call for.