IF YOU’RE OVER 40, the first time you heard the word “isometrics” was probably in the context of an exercise program your Dad used to get the 1970s version of jacked. Contract and hold a muscle, the ...

Isometric, isotonic, and isokinetic exercises refer to the different techniques for activating and strengthening muscles. Isometric exercises, like planks, involve activating muscles with no movement.

Isometric exercises like wall sits, planks, and glute bridges hold the body in one position for a set period of time. Muscles are contracted and engaged, but they don’t lengthen during the exercise.

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