You may think you need an expensive gym membership or fancy equipment to build muscle and workout effectively, but results are possible just by using your own body weight. With that in mind, here are six exercises that will have you building muscle and looking great in no time — sans equipment:

1. Running or walking

Build muscle running

No expensive treadmill or elliptical needed, just your own two legs and a good pair of running shoes. “If you focus 80 percent of your energy on cardio, you will see your body transform,” says Ashley Marriott, a Los Angeles-based fitness trainer and coauthor with Dr. Marc Paulsen of “Dump your Trainer.”

“Look at runners and cyclists; they’re not doing spot training, they do cardio, cardio, cardio," says Marriot. "Most of the people you see in mags that have amazing abs, they’re runners, swimmers, athletes; they are not doing a bunch of crunches. How they got so lean? Their diet is clean, and they get a tremendous amount of calorie expenditure in their cardio.”

Marriot is a huge advocate of one trick: when you do cardio work, pull your navel into your core. Even as you walk or run, don’t just focus on the cardio, think about your abs and pull them in. You’ll see increased strength from that.

To do: Try walking at a quick clip or running a slow jog for 15-30 minutes to start. Add in increments of 5-10 minutes weekly. 

2. Squats

Build muscle squats

Squats are one of the best exercises you can do. It’s easy to progress to more difficult versions over time; and in the meantime, perfect your form for best results.

To do: Stand with your feet shoulder-width apart and put your arms out straight in front of you or behind your head. Begin by pushing your hips and butt back and bending at the knees. Look straight ahead and keep your chest up and back flat. Your back should remain in this neutral position throughout the movement. Squat down as low as you can and then pop back up to the starting position by driving through your heels. Weight should remain on your heels throughout the exercise. (Pictured above is a variation, the jump squat.)

3. Push-ups

Build muscle push-ups

Push-ups work your chest, shoulders, triceps and core for a complete muscle-building exercise. They’re a major deal, so don’t neglect them.

To do: Place your hands on the ground slightly wider than shoulder-width apart and lower yourself until your chest almost touches the floor. Squeeze your glutes together and tense your abs as you lower and raise your body. Keep your elbows close to your sides to protect your shoulders.

If you can’t do a push-up, it’s easy to modify doing the same movement with your knees bent slightly and remaining on the floor, or work up to push-ups by starting on an incline. Use the same technique above against a wall. Place your hands just beyond shoulder-width on a wall, tighten core and press up and lower back to the floor.

4. Crunches

Build muscle crunches

They help with core strength and may tone your midsection, but don’t obsess. They should be one small part of an overall plan to develop core strength, which is important for overall body strength and muscle building.  “Women who want a six pack may be unrealistic sometimes, and I have to tell them, if you’re at a healthy body mass index, and feel good, maybe your genetic makeup is not going to give you a six pack.” And that’s OK.

To do: Lie on a matt or carpeted surface for comfort. Bend knees so feet are flat on the floor. Cross arms in front of chest. Lift your shoulders towards the ceiling using your abdominal muscles and pause at the peak of the movement. Don’t lift your entire back off the floor, as this can cause back strain. Exhale and contract abs as you go up. Inhale and ease slowly back down until shoulders are flat on the floor. Don’t just plop backward; control the movement. Go for two to three sets of 10 to start.

5. Walking lunges

Build muscle lunges

Lunges are great for building thigh muscles says Marriot.

To do: From a standing position, feet hip-width apart, take a giant step forward with knee bent at 90 degrees. Keep knees over ankles and shoulders over hips. Take another step and repeat until fatigued. Go for three sets of 10 with each leg. Also look to cardio work, like hiking or walking up and down steps in your house to combine leg work with cardio. 

6. Tricep dips

Build muscle tricep dip

“Again, the back of the arm is a place where women carry weight genetically, and that may be the last place that some women lose weight, so watch calorie intake and get more cardio,” says Marriott.

To do: You needn’t use a dip machine or weights but instead, use your own body weight. Sitting at the edge of a chair, place your hands over the edge of the seat, keeping knuckles pointing forward. With legs out in front bent at a 90-degree position and feet pointing ahead, shoulders are down and elbows are close to your side, slowly bend elbows into 90-degree angle, lowering your butt towards the floor. Pause and return to sitting, keeping pressure on the heel of your hands. Try two sets of 10 or until triceps fatigue.

And remember: Before starting any exercise routine, check with your doctor.

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