When you don't feel like exercising, remember that any amount of activity is better than skipping your workout altogether. Try these effective exercises that require no equipment.

Rotating Jump Squats

Jump squats get your heart pumping by working the large muscles in your lower body.

• Stand with your feet hip-width apart, and sit into a squat as if you were sitting back into a chair.
• As you return to the starting position, jump into the air. Do four jump squats.
• Next, turn 90 degrees to the right as you jump. Do four jump squats until you are back to your starting position.
• Now jump four times while turning to your left.

Modified Burpees

Traditional burpees can be too difficult for many people. Modified burpees can still increase your heart rate and work your upper body and core.

• Bend down and place both hands on the floor, just in front of your toes. Move into a plank position by stepping one foot back at a time.
• Hold here, or drop to your knees and do one modified pushup. Raise back into plank position.
• Jump both feet forward to meet your hands, or step one foot forward at a time.
• Return to standing and repeat ten times.

Plank Combo

Challenge your core for two minutes.

• Get into a plank position on your hands and toes. Your body should be straight from head to heels. Hold for 30 seconds.
• Shift the weight to your right hand as you roll onto the outside of your right foot. Extend your left arm towards the sky. Hold the side plank for 30 seconds.
• Repeat the forward plank, then perform the side plank on the other side.

Plank Jacks

Plank jacks work your core and upper body, while the rapid movement of the lower body provides a cardio workout.

• Hold the plank position on your hands and toes. Jump both feet out to the sides like a jumping jack.
• Jump both feet back to the center. Continue the jacks, jumping out and in quickly.
• Do ten repetitiions.

Too tough? Decrease the intensity by stepping one foot out and back at a time.

Lori Rice, M.S., is a nutritional scientist and author with a passion for healthy cooking, exercise physiology, and food photography.