Try This No-Equipment Leg Workout When You Can't Make It to the Gym

When the gym's leg press machine has a line three people deep, the kettlebells are nowhere to be found, and the smith machine is on the fritz, you're probably ready to call your leg day quits. Instead of heading home and plopping yourself on the couch, break out the yoga mat and start building muscle in your lower body with these equipment-free exercises.

Each of these moves is designed to work your glutes, quads, hamstrings, or calves (Bonus: Some exercises work double duty and strengthen your core.) Start off with the beginner moves such as donkey kicks and curtsy lunges to warm up your muscles and then progress to more advanced exercises, aiming to complete 15-20 reps of each. (Ready for more? Try this 30-day booty-building challenge.)

Targets: abs, glutes, hamstrings, and quads

A. Stand with feet slightly more than shoulder-width apart, toes pointed out about 45 degrees.

B. Squat, keeping abs engaged, hands on hips and knees aligned with ankles.

C. Squeeze glutes to stand up. Do 15 reps.

(Related: 12 Ways to Spice up Your Squats for Better Results)

Targets: glutes

A. Get on all fours on mat (hands under shoulders, knees under hips).

B. Keeping right knee bent 90 degrees, flex right foot and lift knee to hip level.

C. Lower knee without touching floor; lift again. Do 15 reps. Switch legs; repeat.

Targets: glutes, hamstrings, and quads

A. Stand with feet hip-width apart, hands on hips.

B. Lunge back with left leg, crossing left foot behind right; bend both knees 90 degrees, keeping right knee directly above right ankle. Return to start.

C. Switch legs; repeat. Do 20 reps, alternating sides.

(Next time you hit the gym, try Alison Brie's intense curtsy lunge variation.)

Targets: glutes, hamstrings, quads, and calves

A. Stand with feet more than shoulder-width apart, toes pointed out 45 degrees.

B. Lift heels off floor and squat, keeping knees above ankles.

C. Squeeze glutes to stand up; lower heels. Do 15 reps.

Targets: glutes, quads

A. Start on all fours (hands under shoulders, knees under hips).

B. Keeping right knee bent, flex right foot and lift knee to hip level.

C. Lower right knee to outside of left knee, then diagonally lift it back to hip level. Do 15 reps; switch legs. Repeat.

(To up the intensity of donkey kicks, steal Hailey Bieber's hack.)

Targets: glutes, hamstrings, and quads

A. Stand with feet hip-width apart, hands on hips.

B. Lunge back with left leg, crossing left foot behind right; bend both knees 90 degrees.

C. Push off with left foot to bring left bent knee to hip level in front of you.

D. Hold for 2 counts; return to curtsy lunge. Do 15 reps. Switch legs and repeat.

Targets: glutes, hamstrings, and quads

A. Stand with feet slightly more than shoulder-width apart, toes pointed out 45 degrees.

B. Squat, keeping knees above ankles.

C. Stand up. Do 15 reps.

D. Then do 15 more reps, jumping between squats.

(Love frog jumps? Try these plyometric leg exercises during your next workout.)

Targets: abs, glutes, and quads

A. Start on all fours (hands under shoulders, knees under hips).

B. Keeping right knee bent 90 degrees, lift right knee out to side at hip level.

C. Straighten right leg, point toes, then lower foot to floor.

D. Lift leg back to hip height. Bend knee and return to start. Do 15 reps. Switch legs; repeat.

Targets: glutes, hamstrings, and quads

A. Stand with feet hip-width apart, fists in front of chest.

B. Lunge back with left leg, crossing left foot behind right; bend both knees 90 degrees.

C. Push into right foot as you lift left leg, kicking it in an arc out to the left side.

D. Return to curtsy lunge. Do 15 reps; switch legs and repeat.