Try “Hurricane Sprints” For a Super Challenging Sprint Workout
Doing sprint intervals on a running track or the treadmill at the gym is a popular way to get an effective, short cardio workout. There’s one major gripe: you’re mainly working out your legs. With “hurricane sprints”, your upper body and core can actively join the fun.
from Lifehacker http://ift.tt/1WGEqj8
via IFTTT