Feeling sore and tired? You may be over-training. Read on to find out the signs of over-exercising, and how you can get back on track.

Do you find that you're pushing yourself to work out longer and harder? Are you plagued by relentless fatigue, pain that hangs around for days and a puzzling lack of results? Unfortunately, tiredness, throbbing biceps and a frozen weight scale aren't signs of workout success -- they're actually traits of over-exercising.

What is over-exercising or over-training?

According to Sammie Kennedy, CEO and creator of Booty Camp Fitness (www.bootycampfitness.com) in Toronto, over-exercising or over-training is "exercising every single day for hours -- one, two, three hours on end -- and never taking rest time to give your body the opportunity to recover from your workout."

Many people get on a workout kick. They want to lose weight and are completely focused on their goal, but they make a big mistake: they exercise every day.

"That's where things start to get a little bit dangerous," says Kennedy. "It's hard to understand that taking days off is part of the process, and that's when people get into over-exercising."

What are the signs of over-exercising?

Aching leg and arm joints, tender muscles and an unshakeable feeling of fatigue are the first symptoms that you're taking your workout routine too far. At this point, exercise starts to cross over from being a beneficial activity to a dangerous one.

"Instead of becoming stronger and more powerful, the body starts to rebel against what you're doing. It becomes weaker, more fragile," says Kennedy.

Muscles and joints need time to recover from the stress that exercise inflicts. If they can't recuperate, your strength and endurance will suffer the next time you hit the gym. You'll feel sluggish and drained -- not exactly what you had in mind when you started breaking a sweat.

A scale that won't budge is another attention-grabber. Despite the hours and effort you're putting in, if you're over-exercising your waistline likely isn't shrinking. One week you're losing weight, the next you're stuck on a plateau or, even worse, gaining weight.

"Over-exercising affects your hormonal systems and often you'll start gaining weight instead of losing weight," says Kennedy.

Feeling frustrated, some individuals will ramp up their exercise efforts even more in a desperate attempt to see results. Unfortunately, this behaviour is counter-intuitive, sparking a vicious circle where weight loss remains elusive and where pain -- and in some cases, injuries -- becomes the norm.

What are the dangers?

The real dangers to your health are harder to spot. Over-training can result in hypothyroidism, overeating and an increase in the risk of respiratory illness, says Kennedy. In terms of hypothyroidism, excessive exercise can disrupt and slow down the normal operation of the thyroid gland. If the thyroid doesn't produce normal amounts of hormones, the body's internal systems can be knocked off course, leading to fertility problems, heart disease and obesity.

Over-eating is another danger. "The more demands that you put on your body, the more calories it's going to want to recover, so over-eating and over-exercising tend to go hand in hand," says Kennedy.

It's quite common for an over-exerciser to gorge on food after a particularly extensive workout session. In most cases, the calories consumed during these huge meals greatly overshadow the number of calories being spent through exercise, so weight gain and weight-related health issues, like diabetes, can develop.

Extreme workouts can also make you vulnerable to respiratory infections and viruses, such as colds and influenza. "Over-training lowers your immune system," says Kennedy. "You can easily catch respiratory infections during hard training in gyms where the air circulation isn't great."

Get back on track

Thankfully, it's easy to pull the plug on over-exercising. Your first step? Go cold turkey and take a break.

"It's hard for people to do, but taking up to a week off is key," says Kennedy. "Let your body recover, eat healthy and boost your immune system by getting rest."

After this brief spell on the sidelines, you can start exercising again, but be sure to scale down the frequency and exertion of your workouts. "Work out three to five days a week, and take a rest day at least twice a week," says Kennedy.

As for how long you should work out, Kennedy says that somewhere between 30 to 90 minutes is ideal, but going beyond that hour-and-a-half mark swerves back into over-exercising territory.

"You don't have to be there all day," she says. "You can do an hour spin class or a 20-minute high-intensity interval class or a combination of 45 minutes of weights and 45 minutes of cardio."

It's also important to remember that you should never work the same muscles two days in a row because it can lead to injury and diminished results. The best way to eliminate this concern is to switch up your routine or do a program that's continually evolving and changing.

"Do something different," says Kennedy. "If Zumba's your thing, try kick-boxing. Change it up. Boot camps are always evolving; every day is different, so your body doesn't have the opportunity to plateau. It's very efficient and you don't need to do it every day."