Gym class pull-ups may still haunt your dreams, but upper-body strength is totally achievable, even with no access to a gym.

Bodyweight workouts have been shown to be just as effective as other strength training for muscle mass, physical fitness, and performance.

Fortunately, you don’t have to spend hours in the gym to strengthen your upper body — you just need to get a little creative.

We tapped Dan Castillo, certified personal trainer and instructor at Barry’s Bootcamp and CityRow in New York City, to come up with an efficient and effective 7-minute upper-body workout that follows the science.

1. Long jump into backward crab walk

Start with feet hip-width apart. Squat until your butt is at or below knee height. Using arms to generate momentum, jump forward as far as possible and land in the same squat position.

Once you’ve landed, drop hands to the floor (wrists under shoulders) and lift hips up to knee height to come to a reverse tabletop position. Carefully crab-walk backward to the starting position, then repeat.

Alternatively, instead of doing the crab walk, you can run backward to return to the starting position.

2. Hands-under-table biceps hold

This is a creative way to activate your biceps.

Stand with feet directly beneath hips and place both hands flat underneath a table, desk, or other flat, heavy object, with palms facing up.

Keep elbows close to your sides and at a 90-degree angle. Press your palms upward against the surface and pulse, keeping core engaged and back straight.

3. Triceps push-up

Start in a high plank position with hands directly under shoulders, core engaged, and neck relaxed. Lower your chest to the floor, keeping elbows as close as possible to rib cage (you should really feel this along the backs of your arms).

To make it easier, drop to your knees — but be sure to keep core tight and maintain a straight line from shoulders to hips.

For an extra challenge, lower very slowly for 3 counts, and then push back up in 1 count.

4. Shoulder I-Y-T

Lie facedown (forehead to the mat) with arms extended forward above head, hands in fists, and thumbs pointing up to the ceiling, so arms form an “I” shape.

Raise your arms as high as you can, hold for 1 count, and then lower them back to the floor. Next, make a “Y” with your arms and raise and lower them, and then do the same in a “T” position. Continue to repeat the letters.

5. Squat jack

Stand with feet together beneath hips and arms at your sides. Jump feet apart and send hips back to drop into a squat position with feet slightly wider than hip width and arms out in front of chest.

Quickly jump back into the starting position with feet together beneath hips and hands at sides. Repeat.

6. Seated towel hammer curl pulse

Sit in the center of a towel. Grab one end of the towel with each hand, with palms facing inward and thumbs toward the ceiling.

Maintain a 90-degree angle with your elbows and keep them close to the sides of your rib cage. Pull each end of the towel up toward the ceiling, making mini pulses up and down.

7. Triceps dip

Stand facing away from a sturdy chair, couch, or table. Place your hands on the surface, directly under your shoulders, with fingertips pointing toward your body. Extend legs forward, keeping toes flexed upward and heels on the floor.

Slowly bend elbows to lower your butt toward the floor for 3 counts, then push back up quickly for 1 count. Repeat.

To make it easier, move your feet closer to the chair and add a slight bend in your knees.

8. Push back push-up

Start in a high plank position, with wrists under shoulders and feet wider than hip width. Lower into a push-up. Press into your palms to send hips and butt back, bending knees wide (like a crouching position) and then lifting hips up into a Downward Dog Pose.

Make sure your head is positioned between your shoulders — biceps should be outside ears and elbows soft. Shift forward to return to the starting high plank position. Repeat.

9. Jump switch lunge

From a standing position, take a big step back with left foot to lower into a lunge, with knees bent at 90 degrees and hands in front of you or on hips for balance. (You should feel your body weight in your right heel.)

Quickly drive through right heel to jump up and switch your feet, lowering back into a lunge position with left foot in front. Repeat.

10. Bent-over row

Grab two dumbbells, gallon-size jugs of water, or any items of similar weight that have handles. Holding a weight in each hand, with wrists under shoulder, hinge at hips so your upper body is nearly parallel to the floor.

Draw the weights up to your chest, with palms facing away from you (supinated grip), by bending elbows and focusing on squeezing shoulder blades together (like you’re rowing a boat). Slowly lower the weights back to the starting position. Repeat.

11. Side-lying triceps push-up

Lie on your side with knees slightly bent. Bring right arm across chest and place palm of left hand on the floor. Press through left palm until your triceps are fully flexed and your upper body lifts up a little, then slowly lower back to the starting position. Repeat.

12. Pike push-up

Start in a high plank position with wrists under shoulders and core tight. Step feet forward and send hips up so you’re in a pike position, with hands directly in line with shoulders.

Do a push-up so that your head lightly touches the floor a few inches in front of your hands, then push back up to pike. Repeat.