A lot of people swear by fasted cardio—that is, running on a treadmill or hopping on an exercise bike before eating anything. Some say this burns fat faster, though the science on that is inconclusive. But what about getting your strength workout in before eating? Could you hit your bench or squat PR before having anything of substance in the morning?
Followers of intermittent fasting have said that lifting weights in a fasted state makes them hungrier (literally) and meaner when stacking plates. Conventional wisdom, though, tells us it’s better to stack pancakes, down smoothies, and pound protein shakes an hour or so before the gym to give the body optimal fuel.
So how would one press iron without their eggs and oatmeal? We talked to Ashleigh Gass, CSCS, CISSN, CCN, CNS, coach, and co-owner of MOVE Gymnastics Inspired Strength Training in Clearwater, FL., for tips on fasted strength workouts.
If you’re looking to change your physique, you should know that fasted workouts—any form of exercise that takes place 12 hours after your last meal—won’t do much to get you shredded.
“From a body composition standpoint, research isn’t supportive (or at best, it’s mixed),” says Gass. Two studies in the Journal of the International Society of Sports Nutrition—one on male bodybuilders trained in both a fasted and fed state and one with aerobically trained women—found body composition changes to be unchanged or similar between the fasted and non-fasted groups.
Additionally, Gass pointed out, there’s research that indicates fasted strength workouts could prevent you from making strength gains and may cause you to lose lean muscle mass because of a lack of nutrients while working out. You also run the risk of not being able to keep up during long workouts—predominantly those lasting over an hour. However, Gass says that research on this is still inconclusive.
You’ll be able to lift weights while fasted so long as you’re not exhausted or starving, but if you’re going into a heavy lifting session it’s generally smarter to a least have some quality food in your system to power your lifts. “Intense strength-training workouts can be extremely and unnecessarily challenging fasted,” says Gass.
So does Gass recommend you eat a full breakfast before hitting the Iron Paradise?
“I’ve concluded that fasted lifting needs to be a choice based on lifestyle and schedule,” she says. “If lifting while fasted is desired, I’d recommend a scaled approach, where intensity of training is gradually increased to determine work capacity and recovery ability.”
How well your digestion system works is also another indicator of whether lifting weights fasted will be efficient for you. “Many people just don’t like training with food in their stomachs,” she says. Gym newbies, though, should always make sure have something in their stomachs before lifting.
“If you’re new to training, it’s likely unwise to jump into your first intense training experience in a fasted state,” Gass says. “You may find yourself flat out of energy at best, passing out at worst!” Stay away from any lifts you’re not used to doing regularly and perform familiar lifts with familiar intensities and rest periods. “See how it goes, and proceed from there.”