If hard-core CrossFit workouts aren’t your thing and the weight room at the gym gives you anxiety, no problem. It is possible to tone up and get stronger without major heavy-lifting—in fact, research backs this up. Doing high reps of light weights is just as beneficial as doing fewer reps of heavy weights, according to a new study from McMaster University in Canada. Researchers found that both lead to the same amount of muscle growth. 

There’s just one catch: Whatever amount of weight you’re picking up, you’ve got to do enough reps with it that you hit muscular fatigue. (In the 12-week study, the exercisers who lifted heavy weights did eight to 12 reps while those lifting lighter weights had to do 20 to 25 reps.) It can be tough to push yourself to get to that point where you can’t do one more rep, so we talked with instructors at some of the country’s top barre studios for their best advice about how to push yourself to your limit. They’re all you need (plus a few lightweight dumbbells) to effectively sculpt muscle.

1. PUT SOME THOUGHT INTO IT.

“When lifting light weights, have a high repetition goal in mind, then challenge yourself to actually do three to five more reps than that goal during every set. Then in between sets, think about reducing your recovery time so that the muscle fibers have less time to restore. To help yourself keep going, I suggest repeating a mantra to yourself, like, ‘The mind gives up before the muscles do,’ ‘Shaking means changing,’ or ‘I can and I will!’”

—Katelyn DiGiorgio, Director of Training & Quality Assurance at Pure Barre

2. DON'T HOLD YOUR BREATH.

“Breathing helps you get through the reps. Remember to exhale as you contract the muscle that's being addressed and inhale when you release. It helps your mind focus on your breath instead of the aching muscles. It also keeps you alert and focused so your form doesn't go out the window.” 

—Caitlin Potosnak, a barre instructor at The Sports Center at Chelsea Piers in New York City

3. FOCUS ON FORM.

“The clearest path to fatigue (and results!) in a lightweight workout is good form. Most people can bore themselves to tears doing traditional biceps curls with 3-pound weights for quite some time before feeling much of anything. In this exercise, for example, if you keep your elbows tight against your body and don't extend your arms fully, you're cheating yourself out of results. Do it correctly, and you won't want to stick with it for more than a minute.”

—Kiesha Ramey-Presner, Vice President of Teacher Development and Master Instructor at Bar Method

4. PUSH PAST THE SHAKE.

“You know it's working when you feel a lot of heat and feel like you can't do another rep. You should feel extremely challenged but not to the point of sacrificing form. Once your muscles start shaking, you are close to overload and probably only have a few reps left in you. Visualize yourself finishing the set. It may be more mental strength that will get you through to see the results you want to achieve; beautiful, sculpted, strong muscles.”

—Tanya Becker, Cofounder and Chief Creative Officer of Physique 57

5. HIT RESET WHEN NECESSARY. 

“Working with light weights may feel very ‘doable’ to start. The challenge is in how many reps you can produce over an extended period of time. As time goes by, you'll start to feel like your muscles are burning. As the burn continues, you will get to a point where it feels very difficult to sustain the position and complete each rep while maintaining proper form, and you may find you need to stop the exercise, allow your muscles to relax for a moment, and then reset.”

—Emily Sferra, Director of Training and Master Instructor at FlyBarre

6. STOP WHEN YOUR FORM SUFFERS.

“In the strengthening phase of an exercise, fatigue sets in when a repetitive movement leads the muscle group to the point of failure. The key is to establish a solid postural foundation for the exercise and work to the point where that posture needs to be compromised in order to do one more rep. If you need to compromise your foundation in order to complete one more rep, you have reached the point of muscular failure. The moment you compromise posture and alignment, the working muscles have reached failure and other muscles are recruited in order to do more reps.” 

— Fred DeVito, teacher and co-creator of Core Fusion Barre at Exhale