Why it's a winner: Squats work multiple muscle groups -- the quadriceps, hamstrings, and gluteals -- at the same time.
How to: Keep your feet shoulder-width apart and your back straight. Bend your knees and lower your rear as if you were sitting down in a chair, keeping your knees over your ankles.
Begin by lying on your back with feet flat on the floor and palms supporting your head. Press your lower back into the floor. Contract abdominals and raise first your head (tucking your chin slightly), then your neck, shoulders, and upper back off the floor.
Abdominal Crunches: Troubleshooting
Keep your neck in line with your spine. Don't stick your chin out. Don't hold your breath. To keep chest and shoulders open, keep your elbows out of your line of vision.
Why it's a winner: Rowing strengthens the back, shoulders, biceps, and core muscles.
How to: Use a resistance band for this exercise. You can attach the resistance band to a secure place such as a strong banister or secure door, Seated with the exercise band firmly anchored, place hands and feet shoulder-width apart. Keeping rear-end muscles and abdominals engaged, move handles to your body by bending and straightening your elbows, keeping your torso stable throughout the motion.