How to Pick the Right Weight in Class

Between confusing Google Maps directions, questionable shower availability and generally hoping you won’t stand out from the pack too much, there’s a lot of nervousness associated with being a class newbie. But that’s where the beauty of group-setting ClassPass workouts really comes into play. Your instructor is armed with a personalized, structured workout the second you walk through the doors. You check in, follow instructions, and get results—no questions or crazy preparation on your part.  

That is, until your HIIT or bootcamp instructor cheerily shouts out before a Tabata, “Okay! Go grab the kettlebell or dumbbell weight right for you!”

Here’s the dilemma. Pick a weight too light, and you’ll barely feel the burn. Pick a weight too high, and ultimately feel embarrassed when you’re forced to drop it mid-set. Ugh. What’s a girl or guy to do?

No fear. Daphnie Yang, personal trainer and creator of HIIT IT!, offers no-frills solutions for finding your perfect exercise weight for your upper body, abs and legs in your next strength training class.

Upper body: Don’t compromise on form

According to Yang, the upper body can be separated into two sections: back, chest and biceps, in addition to triceps and shoulders. Both require a different approach to weights.

“Generally, men and women can go heavier with exercises involving the back and biceps,” she explains. “We use these muscles fairly often in day-to-day life, so picking a dumbbell that’s slightly heavier for these moves can be more beneficial.”

Although Yang suggests pushups as the most effective chest workout, when using a dumbbell or a bar, heavier is often the way to go. “A heavier dumbbell may actually help you perform the move slower and with better form,” she adds.

The lesser-used triceps and shoulders only need light weights. So if you’re instructor gives you an option of 3, 5 or 10 lb. dumbbells for cheer presses, try the 3 lb. set first to see if it’s achievable, and move up accordingly.

Bottom line when it comes to upper body, according to Yang? Don’t compromise on form. “There is no shame in swapping your dumbbells out for a lighter one!”

Abs: Slow and steady wins the race

While the upper and lower body both have somewhat finite ranges to how heavy your weight should be, according to Yang, working the abs isn’t so black and white.

“When performing core moves and using medicine balls, I recommend starting out with a 6 lb. medicine ball or something on the lighter side. This allows you to focus on form first,” she says. Depending on the number of repetitions and what kind of exercise it is (i.e. torso twists, v-ups), you’ll then need to drop—or increase—the weight accordingly.

But when it comes to performing ab workouts with a weight, Yang urges caution at first. “Ab workouts with medicine balls usually force your core muscles to work harder to stabilize. But with any core exercise involving equipment, you have to be careful with momentum,” she says. “You run the risk of hurting your lower back when using too much momentum with any core move. The purpose of the exercise isn’t to toss the ball from side to side, it’s to increase the degree of difficulty of torso and trunk rotation with added weight.”

Bottom line: Focus on the movement and form before weight (at first).

Lower body: The bigger, the better!

From quads to hamstrings to glutes, our legs house some of the biggest muscles in our bodies, so you’ll need to lift big if you want to see big results.

“The glutes, hamstrings and quads are powerhouse muscles that love a little TLC. You’ll need to train them first to increase the calorie burn for the entire workout,” says Yang.

As for selecting a weight, she suggests generally going big but with some slight modifications. “Think of it this way: if the weight is there to merely add weight, like a bar on your back, dumbbells at your sides or a medicine ball in your arm, you can go heavier,” she says. “But if you’re performing a lower-body exercise and using the weight to complete an upper-body exercise simultaneously, like a dumbbell squat shoulder press, choose a weight you’d normally use for the press.”

Bottom line? When it comes to the legs, bigger is usually always better.

Know your audience

While Yang recommends tailoring weight to the particular part of your body you’re training, the most important factor is your type of class.

“If it’s a strength bootcamp class in which you will be performing 12 to 15 reps of an exercise, go heavier,” says Yang. “If it’s a spin or HIIT class, in which the moves will be repeated over and over again for a decent chunk of time—say 20 seconds of shoulder press jumping jacks in a Tabata, performing bicep curl squats for 45 seconds or performing a million tricep extensions in spin class—go lighter.”

Julia Sullivan is a freelance writer and editor in New York City. When she's not picking heavy things up and setting them down again (more commonly known as weight lifting), trying to prepare healthy meals in her doll-sized Manhattan studio or writing about the latest fitness craze, she chronicles her zany adventures as a new New Yorker in her blog, Jules & the City. You can also follow her on Twitter.