10 micro-exercises that are as effective as a 20-minute walk
2. Wall Push-Ups Wall push-ups are a gentle yet effective upper-body exercise that works the chest, shoulders, and arms, ...
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Why You Lose Your Breath Going Up the Stairs -- Even if You're Super Fit
If you're an endurance cardio nut like me, you're in great shape, but sustained exercise like this uses slow-twitch muscles. So, it won't transfer over super well to exercises like stair climbing.