These body type classifications have their roots in discredited pseudoscience—but they're still common shorthand at the gym.

Skeletal muscle, like that in your leg or arm, can heal after injury. Rest is key to that recovery. The idea here is that the heart, too, may have a hidden power to heal—if it can rest.

That’s the window when protein and carbs really matter for muscle repair and growth. When you’re low on sleep, should you power through a lift or give your body the rest it clearly needs?

For lower-body workouts from Stephanie Mansour routines — plus fitness challenges, walking podcasts, meal plans and inspiration — download the Start TODAY app! Large muscles like the ...

Why Protein Matters: Your muscles naturally break down. Eating enough protein helps rebuild and grow them stronger — especially if you're lifting weights.

That study found no significant differences in muscle protein synthesis over time. However, volunteers in that study consumed 1.6-1.8 grams of protein per kilogram of body weight per day, which is ...

Muscle is a soft tissue composed of elongated cells (muscle fibres) that produce force and motion through contraction. Involuntary cardiac and smooth muscles are responsible for contraction of the ...

Superficial back and core anatomy describes the muscles located directly beneath your skin and superficial fascia. They are involved in moving your upper body, maintaining good posture, coughing, and ...

The body of Pope Francis lies in state inside St. Peter's Basilica in the Vatican on Wednesday. (Tiziana Fabi/AFP via Getty Images) ...