Overtraining not only can cause setbacks in training, but it can lead to aching muscles, joints and bones, injuries, mood changes, emotional instability and decreased motivation. Here's how to avoid pushing yourself too much.

For the last 14 years, James T. Hall has been competing in bench press championships, strongman competitions and Highland games.

At 40, this professional athlete from Springfield, Ill. - who has sponsorships from several national and international companies - knows his limits. But he admits to pushing himself beyond what's healthy for a bigger, stronger and faster body.

"Sometimes trying to reach an ultimate goal can lead to overtraining," Hall says.

When this happens, he admits, "you cease making progress, and can even begin to lose strength and fitness."

Overtraining not only can cause setbacks in training, but it can lead to aching muscles, joints and bones and even injury.

Like Hall, LiveStrong.com, the website for the Lance Armstrong Foundation, advises that training too hard often results in injury, loss of strength and an increase in body fat - the opposite result athletes and fitness-seekers normally want to achieve.

Also attributed to overtraining are symptoms that include mood changes, emotional instability and decreased motivation.

More alarming is the risk to long-term health - bone health in particular. According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases, exercising too much can lead to a reduction of bone density, which can cause bone fractures and osteoporosis later in life.

But the notion that more isn't always better may be counterintuitive for the average fitness seeker, especially compared to a sedentary lifestyle. Yet the same risk applies for amateur and professional athletes alike.

Doing it right

If you want to improve strength and endurance through exercise, says Anthony Nizzio - a certified personal fitness trainer and owner of One on One Fitness in Springfield - you need to work up to that goal gradually and give yourself time to train properly.

"Think about your goals and why you are doing it," Nizzio says. "For your average person, any type of exercise that lasts more than an hour is either too much or ineffective."

For the best results, Nizzio says to combine a good mix of strength training, cardiovascular training and proper nutrition:

Strength training with weights or resistance of 30 to 60 minutes, three days a week with rest days between workout days to build muscle. Cardio interval training sessions of 30 to 60 minutes three to five days a week for heart health and muscle conditioning (combine high-intensity exercise intervals - like running, biking, inline skating or fast walking - with slower, more comfortable intervals to achieve cardiovascular fitness). Proper diet, consisting of plenty of protein and "clean" foods (natural sources of vitamins and fiber such as fruits, vegetables and whole grains). For athletes who want to achieve certain goals, Nizzio recommends consulting with a professional athletic trainer or personal trainer who is knowledgeable in the specific sport. "Even if you only use a trainer on occasion, stick to their guidelines. If they're good at what they do, they can help you achieve the next level without taking you past your limits," he says.

One important thing to remember: Stick to a good diet.

"If you train hard and frequently but your diet is out of line, you won't get results. People won't lose body fat or gain strength without making nutrition at least 60 to 70 percent of the exercise to diet ratio," Nizzio says.

Symptoms of overtraining

If you overtrain and don't give your body time to recover, you might experience:

Joint pain and/or muscle pain abnormal levels of fatigue weakness increased body fat depression sleep disruption irritability

If you think you're overtraining, rest for a few days between workouts. For symptoms associated with exercise that go beyond minimal levels of discomfort, seek medical attention.

Repairing the damage

Anthony Nizzio, owner of One on One Fitness says a one- to two-day rest period between workouts can give your body a chance to repair the muscle damage of an intense workout and speed recovery for increased athletic development.