The exercise that sunk me was a seemingly simple, low-intensity movement called the negative pull-up: essentially jumping up to hold my chin above a bar, then slowly lowering myself down using my body weight as the force. The trainer had me doing six sets of four reps each, but by the third set, I physically couldn’t hold myself up anymore without assistance. In hindsight, I should have called it quits, but not knowing that rhabdo even existed, I pushed through it. The next day, my lat muscle was so swollen that it jiggled when I walked, and a few days later, my entire upper body looked like a puffy marshmallow. Despite my friend’s advice and a clueless doctor at urgent care who recommended I go for acupuncture, I headed to the emergency room where they immediately sent me for an EKG and hooked me up to an IV of fluids. With rhabdo, the overworked muscle dies, resulting in a flood of toxins, dead cells, and minerals that the kidneys can’t flush fast enough. The buildup can cause kidney failure, or in other cases, heart failure because of the sharp increase in minerals like potassium. I ended up staying for five days on a round-the-clock IV drip until my levels dropped below the danger threshold. Normal readings of the enzyme CPK (creatine phosphokinase) register at 120 micrograms per liter or less. When I arrived at the ER, mine had skyrocketed to 55,000 and needed to be monitored every six hours. After leaving the hospital, I took another week to recover and de-puff (I’d gained 12 pounds in swelling and fluid retention), then set my sights on how to safely ease back into the gym. I started working out with Paul Kostas, director of personal training at Brooklyn Athletic Club. He helped me gain back my confidence in my workouts and says that many of the techniques he taught me can be translated to working out again after any injury, not just rhabdo. Here’s what I learned: “You have to listen to yourself. When your body starts to say no, sometimes the hardest part is speaking up to a coach or a trainer. In some cases, they might say to keep going, but when you know you’ve hit that point, you just have to stop.” For me, it should have been a massive red flag when I physically couldn’t do the exercise without help from the trainer holding me up. While there aren’t any tried-and-true signs or symptoms that an injury is about to take place, reaching muscle failure is a good clue that you should quit. To determine what’s an acceptable level of soreness, you should pay attention to whether the tenderness is incapacitating. A little bit of stiffness and pain is normal, but if there is any swelling or bruising or you can’t walk—you’ve gone too far. If you’ve already hurt yourself, it’s critical that you take it slow and steady to build back both your physical and mental strength. Paul explained to me that “The biggest mistake I see people making after an injury is trying to pick up right where they left off. You need to ease yourself back in and give your body a chance to rest and re-acclimate. Unfortunately, it takes a lot longer for tissues to heal than you’d like it to, so having patience is key.” You also might need to backtrack even more than where you originally started to allow the body to repair. When you’re interviewing trainers, do your research and don’t forget to ask for their certification. The national certification organizations are the NSCA, ASCM, NASM, and the ACE, and while it’s certainly possible to find a great trainer that’s certified outside of these large organizations, you should be careful. Here’s a list of additional questions to ask a potential trainer: Want to learn more about rhabdomyolysis? Here’s when you should be worried about your exercise habits. Wien specializes in wellness, food, travel, and unique experiences, and authored Gap to Great: A Parent’s Guide to the Gap Year. Her work has been featured in Be Well by Frank Lipman, Forbes, USA Today, Thrillist and The Huffington Post.