Lift heavy or light: what’s the best way?

What’s the best strategy for gaining strength and muscle?

It’s been an ongoing argument in the bodybuilding and fitness world for decades. What’s better for gaining muscle size and strength: heavy or light weights?

Recent research has found that lifting heavy weights is best for gaining strength but that growing bigger muscles can be achieved with heavy or light weights.

“It had long been claimed that to gain muscle you needed to lift relatively heavy weights,” said lead author Brad Schoenfeld. “Science has now shown otherwise.”

The study:

Researchers conducted a meta-analyses of more than 20 studies. The studies all had to meet a strict five-part criteria, including that they all had to involve both strength and hypertrophy training protocols and lasted at least six weeks.

The results showed that gains in strength were significantly greater when participants lifted heavier weights.

The strength gains were measured in 1RM (one-rep max), meaning the most a participant could lift once.

However, when it came to hypertrophy — muscle building — the results were similar between those who lifted heavy and those who lifted light weights. (This finding agrees somewhat with some previous research, which found that you can build muscle and strength using lighter weights.)

The researchers conclude that, while you’re better able to get strong by lifting heavy, you can put on more muscle lifting heavy, medium or light. Or, as the study authors put it, “across a spectrum of loading ranges”.

What does this mean for the everyday exerciser in the gym? Results like might suggest ways to structure individual workouts or design weight training programs — or even confirming the way you currently do things.

Heavy compounds with lighter machine work, for example. This common strategy combines a higher-load (heavier) low-rep exercises with lighter weight, higher-rep exercises within the same session.

Just remember that, no matter how heavy you lift, keep good form and technique throughout your workout.


Schoenfeld, B. et al. (2017). ‘Strength and hypertrophy adaptations between low- versus high-load resistance training: A systematic review and meta-analysis.’
The Journal of Strength and Conditioning Research, August 2017. DOI: 10.1519/JSC.0000000000002200

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