Skip Nav
Workouts
Get a 6-Pack With This Trainer's Intense 7-Move Ab Workout
What It's Like to Work Out Every Day For a Month
Editor Experiments
I Worked Out Every Day For a Month and Was Shocked at What Happened to My Weight
How to Calculate Macros
Healthy Eating Tips
Calculating Your Macros Is Key to Making Good Diet Choices — Here's How to Do It
Advanced Workouts
A CrossFit Coach Crafted This Quick and Intense Workout to Make You Sore All Over
Workouts
I'm a Trainer, and This Is How to Use the Cable Machine For a Full-Body Workout

Physical Effects of Overtraining

This Is Exactly What Happens to Your Body When You Don't Take a Rest Day

If you're someone who has a hard time giving yourself a break, and you've been skipping rest days, then listen up: while we admire your dedication, skipping your recovery is doing you more harm than you think. After all, rest days are when your body actually builds the muscle you've been working so hard to create.

We wanted to find out exactly what happens to your body when you train too hard, so we talked to Michelle Opperman, director of group fitness for Crunch, and Jan Milano, CSCS and sports performance coach at DIAKADI. Did you know the effects can be so severe physiologically and psychologically that there's a name for it? It's called "Overtraining Syndrome."

Want to know what Overtraining Syndrome looks like? Here's what happens to your body when you don't take time to recover from intense exercise (or endurance events!):

  • Glycogen stores are depleted. Opperman and Milano both noted that your glycogen decreases. Glycogen is your body's energy source, and not something you want to eliminate. Milano says "decreased glycogen may contribute to the lowered lactate responses," meaning your muscles fatigue more quickly.
  • Corticosteroids increase. We know that cortisone and cortisol (stress hormones) are not good for weight loss, and even add to belly-fat retention. Milano told us that these elevated levels also depress the immune system by inhibiting the reaction of lymphocytes to antigens (basically, the fighter cells can't fight the bad invader cells). So overtraining equals a higher likelihood of getting sick.
  • Your heart goes into overdrive. "Both resting heart rate and submaximal exercise heart rate are increased," said Milano. Be nice to your heart. Take a breather.
  • Your performance suffers. Opperman told us that when sufficient rest is not included in a training program, your ability to perform (i.e., continue training, growing muscle, getting stronger) plateaus or declines, because your muscles literally cannot recover and regenerate. So things just get worse and worse.
  • You'll lose muscle mass. Consistent breakdown + no recovery = bye, muscles. That's the opposite of what you're trying to do, right?
  • You'll feel AWFUL. The tiny tears in your muscles cannot heal, which results in inflammation, swelling, and tenderness. Opperman says the feeling will "become extreme, lasting for days." She also noted that you'll feel physically exhausted for an extended period as well, which could make it hard for you to perform your day to day functions.
  • It messes with your mind. Muscular fatigue is not the only thing Opperman and Milano warned about. The fatigue and distress extend psychologically, and Milano noted that you'll notice mental changes before physical ones. "Decreased vigor, motivation, and confidence; raised tension, depression, and anger accompany an individual's recovery," said Milano.
ADVERTISEMENT

Do yourself a favor. Go to yoga, don't skip savasana, do your cooldowns, and take a day off to recover. Need some pointers? Make sure you keep our recovery checklist handy, or try any of these recovery essentials.

From Our Partners
Back and Arms At-Home Workout
Breathing and Exercise
How to Do a Single-Arm Row
Workouts to Get Back in Shape
A Trainer's Favorite Dumbbell Exercises
How to Strengthen Your Arms
How Often Should I Do HIIT?
Should I Warm Up Before Weightlifting?
What Are the Best Bodyweight Exercises?
Are Evening Workouts Good For You?
How to Work Out Every Day
Tips For Starting a Gym Routine
From Our Partners
Latest Fitness
All the Latest From Ryan Reynolds