After following this 21-day dumbbell arm challenge, not only will your arms look more sculpted, but you'll also feel stronger. Don't worry if you've never lifted a dumbbell in your life. This arm plan was designed with everyone in mind, whether it's your first time working out or you exercise regularly.

This challenge created by NASM-certified personal trainer Désirée Triolo consists of five basic dumbbell exercises to target your biceps, triceps, back, and shoulders to build your upper-body strength. Over the course of the challenge, you'll increase the number of reps you're doing of each exercise, eventually working up to three sets of 15 reps for each exercise.

Ahead, you can find a detailed explanation of how to do each of the five exercises, followed by the three-week plan. The first step is choosing the appropriate-size weight - Triolo said you want a dumbbell that fatigues your muscles by the end of the last two reps. She suggested beginners start with five-pound dumbbells and more advanced lifters go heavier at 15 to 25 pounds. If the challenge ever feels too easy (because you're gaining strength!), that's your cue to increase the weight of the dumbbells. Likewise, if you find your muscles are fatiguing too early, decrease the weight amount.

This challenge incorporates two rest days per week, and Triolo said, "My professional opinion is to alternate upper-body and lower-body training days to improve your overall fitness level and to avoid creating muscle imbalances," which is why you'll see "lower body" listed on the plan. On these days, you can do lower-body exercises (like this dumbbell butt workout) or go for a walk, run, bike ride, or hike.

Equipment needed: Dumbbells

Directions: After warming up for a few minutes with some neck circles, Cat and Cow, and arm circles, perform all five of the dumbbell exercises listed below for the designated amount of time per day. After each day's workout, stretch out your upper body with these upper-body stretches.

• Bicep curl

• Bent-over row

• Overhead shoulder press

• Upright row

• Triceps kickback

Day Reps Day 1 3 sets of 8 reps of each exercise Day 2 Lower body Day 3 Rest Day 4 3 sets of 8 reps of each exercise Day 5 Lower body Day 6 Rest Day 7 3 sets of 10 reps of each exercise Day 8 Lower body Day 9 Rest Day 10 3 sets of 10 reps of each exercise Day 11 Lower body Day 12 Rest Day 13 3 sets of 12 reps of each exercise Day 14 Lower body Day 15 Rest Day 16 3 sets of 12 reps of each exercise Day 17 Lower body Day 18 Rest Day 19 3 sets of 14 reps of each exercise Day 20 Rest Day 21 3 sets of 15 reps of each exercise

Keep reading for instructions on the five different variations.

Bicep Curl

• Stand with your feet hip-distance apart, holding a dumbbell in each hand at the sides of your body.

• Keeping your elbows close to your ribs, bend your elbows and slowly raise the dumbbells to your shoulders.

• Moving with control, lower back to the starting position.

• This counts as one rep.

Bent-Over Row

• Stand with your feet hip-distance apart, holding a dumbbell in each hand at the sides of your body. Lean forward, bending both knees, keeping your back flat.

• Extend your arms in front of you so they're parallel with your thighs.

• Pull your elbows behind your back, raising the dumbbells toward the sides of your ribs, squeezing your shoulder blades together. Be sure to keep your elbows in and pointed upward, and don't arch your back.

• Slowly lower the weights back to the starting position.

• This completes one rep.

Overhead Shoulder Press

• Stand with your feet hip-distance apart, holding a dumbbell in each hand just above your shoulders, palms facing in.

• Straighten your arms above you.

• Bend your elbows, coming back to the starting position.

• This completes one rep.

Upright Row

• Stand with your feet hip-distance apart. Hold a dumbbell in each hand with your palms facing your body, shoulders over your pelvis, and a slight bend in your knees.

• Keeping the dumbbells close to your body, raise them toward your shoulders, bending your elbows out to the sides. Slowly lower them to the starting position.

• This counts as one rep.

Triceps Kickback

• Holding a dumbbell in each hand, hinge forward from your hips, bending your knees slightly. Bend your elbows behind you.

• Straighten your arms behind you with your palms facing in. Your arms should be parallel to the floor. Squeeze your triceps, then return to the starting position.

• This counts as one rep.

The post Sculpt and Strengthen Your Arms With This 3-Week Dumbbell Challenge appeared first on PopSugar