While walking or using the stair-climber or another cardio machine, you might focus on your breathing or heart rate to gauge how hard you’re working. That’s a perfectly good approach—but it won’t tell ...

This simple, often neglected skill can pay huge dividends later in life. By Hilary Achauer Len Kaplan began having difficulty walking in a straight line when he was in his 50s. Scoliosis combined with ...