You have set a goal of going to the gym five days a week. But on day five, you wake up feeling bad. Should you exercise anyway or stay in bed and recover?
That depends on the disease, according to Dr. Michael Jonesco, a specialist in sports and internal medicine at The Ohio State University Wexner Medical Center.
“I trust the ‘neck check’ rule of thumb,” Jonesco told LiveScience. “That means any [illness] in the neck and above is usually a general guideline that is probably safe to follow.”
For example, if you have a sore throat, runny nose, headache, or ear infection, but no fever, you’re probably okay to exercise in most cases.
Related: Why do you sometimes gain weight after exercising?
But for an illness with symptoms below the neck, you’ll probably want to stay home.
These include “things like severe gastrointestinal symptoms, significant myalgia [muscle pain] or body aches, even fever, which is a sign of systemic illness, you know, that your whole body is mounting this inflammatory response to try to cure a systemic bug,” Jonesco said. “These are all things we say, look, probably [take] 48 hours of rest and reevaluation”.
The reason this rule of thumb works is that most problems above the neck do not involve the heart Y lungs. “That’s really what we’re trying to protect,” Jonesco said.
Even digestive discomfort can affect these organs because it can lead to dehydration, which puts stress on the heart. (Also, let’s face it: If you throw up and run to the bathroom every five minutes, your workout probably isn’t your first priority.)
Of course, the neck check is more of a guide than a hard and fast rule. If you have a stuffy nose that makes it hard to breathe, for example, that could be a reason to skip your workout.
So what’s the harm in exercising when you’re sick? Besides the fact that it can make you miserable, it can make you even sicker. Studies have shown that running a marathon, for example, suppresses the immune system and puts people at higher risk of infection for up to three days later.
Although your regular workout probably won’t be a full marathon, working out while you’re sick can put similar stress on your system. “His body is so busy putting energy into those systems necessary for exercise that it has to take that energy from other systems,” Jonesco said.
Even if you don’t get sick anymore, you probably won’t get the exercise benefits you’re looking for in the first place. The calories you burn are likely to come from a rupture of the muscles, for one thing. Also, the main rewards of exercise come from recovery, and it’s harder to recover from a workout when you’re sick.
“You’re not really seeing a benefit, because all you’re really trying to do is survive that one-on-one session,” Jonesco said. “You’re not really training the body to the point where it can recover properly.
“When in doubt, I probably won’t,” he added. “If you’re really not sure if he should exercise, his body is probably telling you he’s not ready.”
But if you’ve been listening to your body for a few days and feeling better, it’s not time to push yourself to the max in your gym session just yet. Jonesco recommended taking it day by day.
“Don’t expect to go back to your previous level,” Jonesco said. “It’s going to take time to rehydrate, to refuel the body, the glycogen stores, the energy stores.” (Glycogen is the sugary substance your muscles use to store energy.)
“So on your first day back, I usually suggest starting at about half the intensity of your typical training, knowing it will take a day or two to get back into the flow of things,” Jonesco said. “And then the next day you can increase that to about 75% and then go as tolerated.”
Originally published on Live Science.
