Joe Dowdell

Joe Dowdell is president of Peak Performance Strength & Conditioning Center in New York City, as well as the trainer for celebs like Anne Hathaway. His advice? Timing is everything. 

In the beginning of your workout, cut your rest time between sets by about 20 to 30 seconds when your muscles aren't exhausted. Then towards the second half of your routine give yourself a little extra rest time, about 40 to 60 seconds, as your muscles become more tired. This method is known as density training and it actually cuts your workout time down by almost 20%. By forcing your muscles to kick it up a knotch, you'll improve your endurance as well. 

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