In adults with overweight or obesity, doing resistance training for 60 minutes three times a week for a year does not lead to a meaningful improvement in overall cardiovascular risk markers, even though it reduces body fat and increases muscle strength.

For adults with overweight or obesity, doing 30 minutes of cardio and 30 minutes of strength training three times a week for a year has the same effect on overall cardiovascular risk as doing 60 minutes of cardio alone.

If you're over 60 and lifting weights, doing it more than twice a week probably won't make you any stronger or give you bigger muscles than doing it just twice a week.

Doing strength training three times a week for three months can help improve muscle size, strength, belly fat, cholesterol, blood sugar, and overall metabolic health in women around 69 years old who are otherwise healthy.

In adults with obesity, doing both cardio and strength training for ten weeks leads to a measurable increase in muscle strength, while doing only cardio does not produce the same increase.

Doing short, simple strength workouts just twice a week might be enough to build muscle and get stronger — even if you're already used to longer, more intense routines.