If you lift the same total amount of weight, lifting heavier weights (80% or more of your max) makes you stronger in a single big lift than lifting lighter weights—but lifting very light weights and light weights (under 60%) give you about the same strength gains.

Lifting heavier weights makes untrained men much stronger than lifting lighter weights over 8 weeks, even if both types of training are done until you can't lift anymore.

Maximal strength gains (1RM) are greater when training with higher relative loads (>80% 1RM) compared to training with lower loads, even when total volume and proximity to failure are matched.

Lifting heavier weights (60-80% of your max) makes you stronger than lifting lighter weights, even if you do the same total amount of work, especially after 12 weeks of training.

Lifting heavy weights three times a week for six weeks makes untrained young men much stronger than lifting light weights, even though both groups gain about the same amount of muscle size.

When beginners lift weights for 10 weeks, doing fewer reps with heavier weights (like 4 or 8 reps max) builds more strength than doing more reps with lighter weights (12 reps max), even if the total work is the same.