The secret of thin waist hides in the type of exercises you do. When you control your diet, you're getting rid of some of the fat in the abdomen.

However, the slim waist will only appear when you start combining a diet with the right exercise. The bicycle crunches, even if they are performed for a long time, are not enough. A long, slow cardio exercises are not also the best way to get a thin waist.

BetterMe App helps women achieve their body goals with ease and efficiency by helping to choose proper meal plans and effective workouts. Start using our app and you will see good results in a short time.

Performing twists until it hurt will not help you as well. Exercises influencing stomach muscles, such as the crunches, act in isolation and do nothing for other abdominal muscles.

If you're tired of useless exercises, this article is for you. Today we want to show you a 7-day challenge, which will make your waist and sides more toned in a week. It consists of 3 simple exercises that do not require special skills or equipment. Scroll down to learn the details.

READ MORE: 10 minutes workout that can help you get a firm lifted butt

#1. Spiderman plank

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Credit: BetterMe

- Lay face down on the ground with extended legs. Point your toes while you place your hands beneath your shoulders.

- Push yourself up into the plank position. Maintaining a tight core and flat back, bring your left knee to your right elbow.

- Pause and slowly return each to the starting point. Repeat with the other side and keep alternating.

#2. Burpees, or squat and thrust

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Credit: BetterMe

READ MORE: This lazy workout can help you tone the whole body

- Stand straight with your feet shoulder width apart and hands by your sides. This is the start position. In one smooth motion, squat down and place your hands palms down on the floor in front of your feet.

- Lean forward, so your weight is on your hands, at the same time jumping your legs out behind you until they are fully extended. Your body should form a straight line with your weight supported on your toes and the balls of your feet and your arms fully extended. (In a push up position)

- Jump your feet out by spreading your legs, so that they are wider than hip width apart, then immediately jump them back together.

- Complete 1 full push up. Jump your feet forward to just behind your hands. Use an explosive motion to push through your heels and return to the start postion. Repeat.

#3. Russian twists

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Credit: BetterMe

- Sit on an exercise mat with your legs fully extended and your upper body upright. Cross your your ankles and raise them off the floor slightly.

- Bend your knees towards you slightly. Lean back about 15 degrees to balance your body. This is the start position.

- In a smooth motion,turn your torso to the left and touch the plate on the floor. Make sure you exhale as you do this.

- Return to the start position inhaling as you do so. Repeat the same movement, this time to your right side, again exhaling as you do so. Return to start position and repeat.

#4. Lying Leg Raises

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Credit: BetterMe

- Lie on your back on a mat with hands under your lower buttocks on either side to support your pelvis.

- Legs straight out in front of you, ankles together and feet slightly off the floor.

- Keep your knees straight and raise your legs by flexing the hips until they are completely flexed.

- Return to starting position.

#5. Cross-body Crunch

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Credit: BetterMe

- Lie flat on an exercise mat on the floor keeping your lower back straight with no arching of your spine and with your knees bent and feet flat on the floor.

- Place your hands lightly on the sides of your head.

- Curl your torso upwards so your shoulders are slightly raised off the floor..

- Raise your knees until your thighs are at a right angle to the floor and your calves are parallel to the floor. This is the start position.

- Slowly move your legs in a pedaling action as if you are riding a bicycle.

- As you do so, exhale and bring your opposing elbow close to each knee by crunching to one side. Left elbow to right knee. Right elbow to left knee.

- After each crunch, return to the start position inhaling as you do so.

- Without pausing, repeat the movement to the other side.

#6. Clamshells / Clams

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Credit: BetterMe

- On a mat or comfortable surface, lie on your left side. Place your left hand behind your head while placing your right hand across your body.

- Bend your stacked knees so that your feet are behind you. Begin the movement by lifting the left knee up while keeping the feet together.

- Pause at the top of the movement and slowly lower your left knee down to the starting position.

#7. Reversed Plank

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Credit: BetterMe

- Your body should be straight, hands right under your shoulders.

- Open your chest and look up.

- Squeeze gluteus muscles and raise your leg. Hold for a few second.

- Repeat with with the other leg.

#8. Plank to Side Plank

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Credit: BetterMe

- Take a positiond of a basic plank.

- Then, raise your left hand and twist your body to the left. You'll be in a position of side plank.

- Put your arm back and repeat on the other side.

- Perform the set without stopping.

READ MORE: 8 moves to make your butt and thighs amazing

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