You made up your mind to get into a better workout routine for summer, and you have a great to-do list. But your to-don’t list is just as important.

Don’t skip your warm up and don’t stretch cold—you’ve heard that stuff before. But there are likely pre- and post-workout moves you’re making to get swole that’d make fitness experts cringe.

So we talked to them for you and got their best advice on what not to do before and after you hit the gym

“After a workout, ignore those highly addictive ‘undercover’ sugar drinks. You didn’t run a marathon—you went to the gym. You don’t need that crap!”

1. Over-stretch.
“Stretching for running, boxing, cycling—exercise where you are using your natural bodyweight and you’re working at full range of motion, from my experience—is not necessary,” says former pro boxer Michael Olajide Jr., co-creator of super-gym Aerospace. “But if you’re doing exercises that limit range of motion and allow you to work in one plane of motion like weightlifting machines—or even heavy free weights and indoor cycling—it’s quite important to get a full stretch to free up and even enhance your range of motion.”

2. Drink too much water.
“Three liters of water a day [is fine] if you are an endurance runner or serious competition is crucial,” notes Olajide. “But three liters of water a day and all you’re taking is an aerobics class, or hitting the weights, or even jogging a few miles is, in my estimation, water-logging you down. Most of us don’t exercise strenuously enough to justify one liter—especially considering we get fluids from other sources as well, like coffee and in fruits and vegetables.”

3. Go in with an empty stomach.
“Not eating before your workout can result in low blood sugar and provide you with a nasty headache, a feeling of being light-headed, dizzy and fatigued and your workout hasn’t even started!” warns fitness expert and Bravo reality television star Craig Ramsay. “Before workouts, eat a banana and a hand full of almonds. A banana will give you a boost with its digestible carbohydrates and fuel your body. Aim to consume your banana on the drive over to the gym (preferably 30 minutes prior to working out). Take in a handful of raw almonds for a little boost of protein.”

4. Drink sugary “health” drinks.
“After a workout, ignore those highly addictive ‘undercover’ sugar drinks,” advises Ramsay. “You didn’t run a marathon—you went to the gym. You don’t need that crap!” Even some green juices contain too much sugar. In fact, most green juices contain four times the sugar that the World Health Organization recommends consuming in an entire day, says Dawn Russell, founder of 8G Greens Superfood Supplement. “The popular green juices sold today have tended to take an easy, unhealthy shortcut, by loading the product up with sugar. You can look at the ingredients they list and you’ll be shocked.”

5. Skip the cool down.
“After weight training, it is OK to do 20 to 30 minutes of cardio, but more than that can impede the progress of muscular hypertrophy,” cautions celebrity fitness coach Jorge Cruise. “Make sure to cool down, targeting the area you were focusing on. A five-minute cool-down of light cardio can help prevent blood from pooling in the veins and get rid of any metabolic waste products. Take time after your workout to sit down, eat your post-workout meal, relax. Your workout won’t be as effective if your body doesn’t get the rest it needs to rebuild.”

6. Fail to listen to your body.
“As much as a phrases like ‘body communication’ sound somewhat New Age, it’s true,” says Russell. “Our bodies always communicate with us, but listening can be difficult with how hectic life can be. Sometimes we just need to shut the world out and listen to our bodies. If your body says stop, then stop. If your body is sluggish and lethargic, then it needs some exercise. Paying attention and being respectful of how our bodies communicate leads to a healthy body and a healthy mind.”