Too busy to work out, you say? Here goes that excuse: Discover Strength offers high-intensity workouts that CEO Luke Carlson promises will get you in shape and keep you there in only one or two sessions a week, 30 to 45 minutes apiece. The coach-led, machine-based workouts are tough — they’re designed to push your muscles to exhaustion — but Carlson, a former trainer for the Minnesota Vikings and strength coach at two high schools, says research shows they deliver all the benefits you’d get from hours of plugging away at a treadmill or free weights. Locations in Chanhassen, Minneapolis and Plymouth.