View post: I Ran in the R.A.D SYNTH Through Weeks of Tempo Training, Easy Miles, and Intervals. They Quickly Became My Go-To for One Type of Run “People don’t take the time to isolate the rear delts ...
Beth Skwarecki is Lifehacker’s Senior Health Editor, and holds certifications as a personal trainer and weightlifting coach. She has been writing about health for over 10 years. It’s easy to almost ...