Don’t exercise more than 2 hours a day- it’s fruitless and possibly harmful.
Most people I know will never be in danger of exercising too much. However, there is a small percentage of people that go overboard. I know a few of them, I can even be one of them at times. There is something called “overtraining”, or overtraining syndrome. It is when you exercise so much that you stop seeing gains, and start seeing negative results- not sleeping well, feeling like you have a cold or flu coming on, getting sick more often, being tired and lethargic, anxious or irritable during the day.
Exercise if vitally important to our well being. I’ve often talked about all the benefits, from the most important-not dying, down to better sleep, better weight, better mobility, better everything. However, as with every other aspect in life, you can overdo it. Most of the people who overdo it are athletes. Most of us would never think to exercise, vigorously and intensely, for more than an hour a day. Training for a Marathon is one example. Elite runners often run for hours every day, up to 6 on the weekend, but they are at greater risk of dying early than the normal population, unlike the 5k’r. Often, they will have a long recovery period following their season, so rather than take their recovery on a weekly basis, it is more on a seasonal basis.
With resistance training there is an even greater need for recover time. While you are exercising you are stressing, damaging and tearing down your muscles. During your rest times they are getting built back up, better than ever. Sort of like remodeling your house. You can do more aerobic exercise than you can resistance, because it isn’t tearing your muscles down to the same extant, so you don’t need the same recovery. How often have you been so sore you couldn’t sit down after running? With aerobic exercise you are just doing what your muscles are used to doing, only for a longer period of time. The general consensus is that you shouldn’t lift every day. For lifting, I would say two hours, 3-4 days a week would be max for most people. Often, lifters will do aerobics on their “off” days, which is fine. I have found at my age, I need at least 2 days totally off. Of course, this is based on doing serious resistance training- where you are using 70-80% of your 1 rep max, and increasing the resistance as you progress. For the uninitiated, this means using a level of resistance where you can’t do more than 10-12 reps, usually in sets of 2-3, with rest between each set. If you can do 20 reps, you need to increase the weight.
This is one of those things that is rather individual. Some people can get away with a lot more training than others. If you are young, healthy, and have been doing your sport/chosen exercise for awhile, you can probably ignore the threat of overtraining for some time. However, if you are experiencing any of the symptoms, back off and see if it improves. It can also be provisional- If you have a lot of other stress in your life, or are very active outside the gym, you may need to cut back in the gym.
No, for the less than enthusiastic exercisers out there who may be reading this saying, “Oh, that must be me, I’ll back off for awhile”, the minimum amount of exercise to see benefits is 150 minutes a week. That means 30 minutes 5 days a week of moderate exercise. There’s a world of difference between that and 420 minutes of vigorous exercise. I feel odd cautioning against overtraining, considering I spend most of my effort trying to get people to move at all. However, I’ve met some seriously overtrained people, and they aren’t getting spectacular results, and that prompted this post. So play hard, as hard as you can, then REST.