5 Things That Happen When You Work Out for Too Long

STACK interviewed Dr. Seedman for this article. which originally appeared on stack.com on 11/9/15.

When you practice a sports skill, generally the more you practice, the better you get at that skill. So it's understandable that many young athletes think this also applies to their workouts—believing that the longer they train, the bigger and stronger they'll become.

However, "more is better" does not apply to strength and conditioning. In fact, training for too long can lead to diminished results, and worse, an injury.

We spoke to Dr. Mike T. Nelson, an exercise physiologist and owner of MikeTNelson.com, and Dr. Joel Seeman, an exercise physiologist and owner of AdvancedHumanPerformance.com, to learn about the problems that occur when athletes spend too much time in the weight room.


Problem 1: The Quality of Your Workout Gradually Decreases

Workouts are designed to put stress on your muscles. That's the only way you can make gains in strength, size and power. However, stress causes fatigue. You might be physically exhausted, grabbing for your knees after a set. Or, you might feel sluggish, slow and weak after finishing a tough workout.

Regardless of the type of fatigue you experience, you can expect it to seriously impact your workout performance as you move through your routine. At a certain point, you won't be able to perform exercises with max strength and speed, and your exercise form will degrade.

"Excessively long workouts create a lot of fatigue that will deteriorate your movement patterns, and your technique is going to break down," says Seedman. "That's not only going to have a negative impact on that workout itself, but the poor technique you engrained in that workout will trickle into the next workout. "

According to Nelson, it's quality versus quantity. As a developing athlete, you might not be able to handle the workouts you see the pros do. "Unless the athlete is pretty advanced, long workouts are not sustainable," he says. "When you hear someone who says they were at the gym for two hours today, you know the quality of work at the beginning and end are dramatically different."


Problem 2: Your Body Might Break Down Muscle For Energy

As you pass the 45-minute mark in your workout, cortisol levels begin to rise in your body. Cortisol is a stress hormone that helps regulate metabolism to ensure the body has sufficient energy to function. The concern is that as cortisol levels rise in a workout, the hormone will signal your body to use your muscle protein as a source of energy—essentially wiping out the positive effects of your workout. The exact time when this begins depends on the intensity of your workout, but the levels gradually increase once it starts.

Nelson thinks the fear is somewhat unfounded. He points to recent research that found increased cortisol levels during a workout are actually a marker of progress. "Cortisol is used to provide fuel," says Nelson. "If you have someone who can increase cortisol levels during training, that's actually a good thing."

However, elevated cortisol levels after a workout can become problematic. "The catch is that as soon as the training is done, we want cortisol levels to go back down to a normal level," he adds.

Seedman explains when cortisol levels remain elevated, inflammation increases throughout the body, which subsequently reduces insulin sensitivity. Insulin helps shuttle the nutrients you eat into your muscles so they can grow. Reduced insulin sensitivity makes it more difficult for this process to occur, putting your body in a situation where it can't create new muscle.


Problem 3: Your Muscles Won't Be Able to Recover

Strength training damages muscles. To gain strength and size, your body repairs the microtears, creating muscle fiber that's larger and able to handle more stress, or it becomes stronger. This rebuilding process occurs when you recover from workouts, not while you're training.

Create too much damage too often, and your muscles won't be able to repair themselves. Seedman says, "You could cause your muscles to decrease in size and strength from workouts that are too long because your body can't recover. It can cause you to go backwards."

That's why it's recommended to prioritize recovery with routines such as foam rolling (shown in the video above) and even light cycling to help muscles repair before the next workout. You don't need to spend allof your time lifting.


Problem 4: It's Not Sustainable

At this point, you might  be wondering about some of those pro athletes, actors and bodybuilders who are famous for their super-long workouts. Yes, it's possible to work out for hours, but only under special conditions.

Athletes don't typically do marathon training sessions. If they do, they normally split them into multiple sessions. For example, we saw Tennessee Titans QB Marcus Mariota do about 45 minutes of speed work. He then took an hour break and ate some food before going into a 60-minute strength session. According to Nelson, a split like that is fairly common.

People who do three-hour workouts need to consider a few things. First, it's an actor or a bodybuilder, they have a specific goal, to look good, which often must be accomplished in a short amount of time. So drastic training methods might be necessary.

These individuals typically pay a ton of money for training and have every resource available to them. They're closely monitored by experts throughout the process to ensure that things don't go awry.

Nelson adds, "They're working with someone who is watching and monitoring everything they do. Their recovery is a lot better. The motivation to do it is usually short-term."

High school athletes typically do not have these resources available to them.


Problem 5: You Might Overreach or Overtrain

Too much training without allowing for recovery causes overreaching. In simple terms, the body shuts down to protect itself from too much stress. It's like post-workout fatigue that doesn't go away. Common symptoms include premature fatigue, lack of strength and endurance, lethargy and elevated resting heart rate.

Nelson explains that stress outside of the weight room can make matters worse. School, homework and sports all take their toll. Young athletes need to realize that training adds to this stress, and doing too much can cause the body essentially to fight back.

Fortunately, overreaching is short-lived as long as you recover. But if you don't, you might slip into the overtraining category. The symptoms are more severe and it takes several weeks or even months to recover.


What Should You Do?

Nelson advises to train smarter, not longer. Workouts should last no less than 60 minutes and no more than 90 minutes. This is sufficient time to challenge your body with quality reps. Anything more, and you'll see diminished returns for your efforts.

If you feel inclined to train longer, it's best to split up your workout. "Instead of a two-hour session, do an hour mid-morning and an hour late afternoon," says Nelson. "You can get much higher quality work done with way."

Nelson recommends prioritizing the frequency, not the duration, of your workouts. It's better to do five or six 60- to 90-minute workouts each week than three two-hour workouts.

All this depends on the style of training, too. Seedman says that if you're doing an intense interval workout or a bodybuilding routine with a lot of reps and little rest, 45 minutes might be all that you need. However, if you're attempting to build max strength and doing only a few reps per set with long rest periods, you might need 90 minutes. If you were to do intervals for 90 minutes, you would quickly burn out.