You don’t have to dedicate a full gym session to training your arms for a better arm swing, posture, and running efficiency.

This high-intensity session is designed for maximum effort, maximum effect—all in minimal time. But it's not easy.

The dead bug is one of the most accessible core exercises for beginners over 50, because youre lying on your back, Tang says. If you have cranky knees or hips, this exercise allows you to lie on the ...