“People think you have to do a long resistance training session in the gym, but that’s not the case,” said Ken Nosaka, professor of sports and exercise science at ECU.
“Simply lowering a heavy dumbbell slowly one to six times a day is enough.”
Nosaka said this new look at muscle could help prevent a decline in strength with aging.
“A decrease in muscle mass is the cause of many chronic diseases, such as cardiovascular disease, type 2 diabetes, some types of cancer, dementia and musculoskeletal problems such as osteoporosis.”
The study examined changes in muscle strength and thickness through constant “maximal voluntary eccentric biceps contractions” performed on a machine.
Two groups performed 30 contractions per week, one group performed six contractions a day for five days a week, while the other crammed all 30 into a single day each week.
Another group only had six contractions one day a week.
After four weeks, the group that performed 30 contractions in a single day showed no increase in muscle strength, although muscle thickness increased by 5.8 percent.
The group that performed six contractions once a week showed no change in muscle strength and muscle thickness.
However, the 6×5 group saw significant increases in muscle strength — more than 10 percent — and a similar increase in muscle thickness of 5.8 percent.
Nosaka said that rest is just as important so that the muscles have time to recover.
“In this study, the 6×5 group had two days off a week,” he said.
“Muscular adaptations happen when we’re resting; if someone could somehow train 24 hours a day, there wouldn’t really be any improvement.
“Muscles need rest to improve their strength and muscle mass, but muscles seem to like to be stimulated more often.”
Australian government guidelines state that adults should aim to be active every day and get 2.5 to 5 hours of moderate physical activity a week.
Nosaka said daily exercise is better than trying to hit a weekly minute goal.
“If you only go to the gym once a week, it’s not as effective as doing a little exercise every day at home,” he said.
