Harley Pasternak, Anna Kaiser and more trainers discuss the exercise classes they despise

Credit: Fitbit

Everyone seems to have that one workout that they just hate – and celebrity trainers are no exception.

Trainer Tracy Anderson has previously knocked indoor cycling, telling Redbook that the classes “bulk thighs” and only “burn calories in the short term.” And now even more of Hollywood’s hottest trainers are getting real about the workouts they won’t do.

“I’m not a huge fan of power-lifting,” AKT founder Anna Kaiser, who trains Kelly Ripa and Shakira, tells PEOPLE. “This genre of training is extremely intense for the sake of pushing one to his or her limits. It’s not training that supports and enhances the movements of everyday life. It also overbuilds muscles in a disproportionate way and puts undo stress on the spine. Is the risk really worth it?”

For Harley Pasternak, who has trained Halle Berry and Lady Gaga, it’s about the temperature. “I hate any exercise in a hot room,” he says. “People think they burn more fat in a hot room because they sweat more. In fact, science tells us the opposite. You actually burn far more fat in a cold environment. And I get overheated in the hot sweaty rooms. Plus they all smell like old socks!”

Sarah Hyland and Corbin Bleu‘s trainer Chad Landers also isn’t a fan of hot classes.

“From hot yoga to hot spinning, any exercise class done in an intentionally hot, humid environment drives me crazy,” says Landers. “First, getting your body temp up near 104 degrees is a recipe for heat exhaustion and could lead to heat stroke.”

“Second, many people do these classes because they are told they will detox via all the sweating,” he continues. “Sorry, but the kidneys, liver and intestines handle that job, not the sweat glands. In fact, the dehydration that can occur in these classes can make it more difficult for your kidneys, liver and intestines to eliminate toxic material!”

RELATED VIDEO: 4 Fitness Gadgets That Make Working Out Fun!

For SIXTY Beverly Hills‘ in-house trainer Danny Musico, Pilates is a no-go.

“I’ll take a bet that 99 percent of Pilates peeps wouldn’t last for 30 seconds in my workout,” says Musico, who has worked with Leonardo DiCaprio and Jessica Simpson. “Pilates trainers claim to be strong and natural athletes, but they can’t make it across the monkey bars. Bottom-line: not a fan!”

Founder of the Lagree Fitness Method Sebastien Lagree despises cycling classes.

“I hate spinning,” says Lagree, who has trained Sofia Vergara and Nicole Kidman. “It hurts my ass and is repetitive. I also find it too hard on the joints and connective tissue.”

Lauren Boggi, who has trained Lauren Graham and Carla Gugino, also doesn’t like riding on stationary bikes.

“I hate indoor cycling,” she says. “Even with all the fun fluff – music, lights, etc. – I feel like a hamster on the wheel, sitting in that bent-over position doing thousands of reps. It overworks my quads and ignores my glutes. And, it hurts my vagina! I think that spinning is great if you’re coming off of an injury, but I prefer full body movement and strength training.”