The study focused on 26 men aged 19 to 35 lifting to their maximum using a leg extension machine, 3 times a week for 6 weeks.
These guys were split into two groups, with half lifting 30% of one repetition maximum (1RM) and the other group lifting 80% 1RM.
Their muscle thickness and strength were tested at the start of training and then in the third and sixth week.
After the six weeks of training, the results revealed that both groups showed a similar increase of muscle growth, but the half that lifted a higher load had a bigger increase in muscular strength.
The group of heavier lifters improved their 1RM strength by approximately 6.8 kilograms.
Heavy lifting could help activate cells that send electrical signals to muscles and muscle fibres those cells supply nerves to, according to the study’s lead author, Nathaniel Jenkins, Ph.D., C.S.C.S.*D.
Basically, muscle activation might be more effective with higher-load training.
But low-load lifting is still effective, as evident in the results. This kind of training can be helpful if you’re recovering from injury, according to Jenkins.
Jenkins also says that it hasn’t been proven yet that lifting lighter weights has the same benefits as heavy lifting.
“Over the long term, training with high loads will help you spend less time in the gym,” Jenkins says. “You see greater strength adaptation accompanied by neural adaptation. That’s going to allow you to use heavier weights and increase your volume, which should allow for more rapid progression,” according to Men’s Health.