Exactly how many seconds to maintain your max heart rate for in a HIIT workout, according to trainers

What to know about your max heart rate and how long you should sustain it for in a HIIT workout, according to fitness trainers.

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16 Upper Glutes Exercises Personal Trainers Swear By for a Stronger Butt

Why your upper glutes deserve more love, and the best exercises to strengthen them.

woman doing an upper glutes exercise with an exercise band.