Even the most unfit of us would have experienced some form of muscle fatigue or soreness at some point. Too much standing, sitting or exercising can lead to muscle fatigue or soreness – a classic symptom that occurs after a period of sustained activity.

Muscle fatigue has a number of possible causes, including impaired blood flow, ion imbalance within the muscle, nervous fatigue, and most importantly, the accumulation of lactic acid in the muscle.

Muscle soreness is caused by microscopic tears of the muscle fibres.

The two types of muscle soreness include acute muscle soreness (pain you feel during and shortly after a workout) and delayed onset muscle soreness (DOMS).

For those of us who are embarking on a fitness regime or are changing workout routines, DOMS is common post-workout.

It comes on 24 hours after your session and can last up to 72 hours.

But, when the ache gets worse beyond this period or you start to feel ill, then something is wrong.

Earlier this week, three University Of Oregon football players in the United States were hospitalised following a series of gruelling workouts.

As semi-professional players, overtraining and unduly harsh practice methods are something they have to undergo as it is often part of the sport.

The Oregonian reported that the university’s strength and conditioning coach put players through exercises, which have been compared to basic military training, including “an hour of continuous push-ups and up-downs”, after which some players “complained of discoloured urine” or passed out.

They were diagnosed as having rhabdomyolysis, a syndrome in which damaged skeletal muscle degenerates and releases myoglobin into the bloodstream.

Myoglobin is the protein that stores oxygen in the muscles, and too much of it in the bloodstream can lead to kidney failure.

However, if victims are treated quickly (usually via IV fluids that contain bicarbonate to help flush myoglobin out of the kidneys), they often fully recover.

Extreme muscle strain, especially in someone who is an untrained athlete, may result in rhabdomyolysis.

Extreme muscle strain, especially in someone who is an untrained athlete, may result in rhabdomyolysis.

Similarly in 2011, 13 Iowa players were hospitalised with rhabdomyolysis after they endured an intense regimen of squats during a team workout, then returned the following day for another intense session, this time for upper-body workouts.

One of those players, cornerback William Lowe, sued the school, saying it had subjected him to unnecessary bodily harm and had failed to properly monitor the workouts.

Lowe, who never returned to the team, said in the lawsuit that he experienced subsequent weight loss, headaches, high blood pressure and continued lower back pain. Lowe and the university reached a settlement last year.

The initial symptoms of rhabdomyolysis can be subtle and may mimic other conditions. The symptoms include muscle weakness, low urine output, fatigue, soreness, bruising, dark, tea-coloured urine, infrequent urination, fever, a sense of malaise or feeling sick, nausea, vomiting, confusion and agitation.

On hindsight, I, too, may have had a brush with mild rhabdomyolysis decades ago du- ring my sophomore year in university.

I was insane enough to enrol in a military fitness class intended for members of the Reserve Officers Training Corps, a programme offered at colleges and universities across the US that prepares young adults to become officers in the military.

I wanted to challenge myself physically, though I’ve no idea why I put myself through such torture, especially since the class was held three times a week, in the dead of winter, at 6am. As I was never a top student, at 20, I foolishly assumed I could earn some bragging rights.

Every student in the class was an extremely fit military cadet, except yours puny, and another chubby fellow who registered to lose weight.

Our training included a day of running 8km, 100 burpees, 100 split lunges and 100 crunches; a day of swimming 50 laps in an Olympic-sized pool (thankfully heated!) and another day of various military drills such as 400m spider crawls, Indian runs, etc.

The first class saw me throwing up; in the second, I barely managed 30 laps in the pool; and the third class had me akin to a flattened spider – I passed out for a few seconds.

The chubby fellow quit after a week, but I held on doggedly. By week three, I was doing slightly better, but at the end of every class, I felt as if I’d been given a few strokes of the rotan. I was constantly nauseated, tired, in pain and lost my appetite.

Another week passed and I couldn’t get out of bed. Alarmed, my roommate dragged me to the medical centre while chiding me for taking “that senseless class which makes no contribution to your IQ”.

Apparently, I was suffering from overtraining and exhaustion, was given vitamins, and told to rest.

Not a quitter, I skipped classes for two weeks and resumed again, eventually completing the class as the slowest and lightest of the pack of 40. But, for not quitting, I got an A.

Exercise is good for you, no doubt, and you can become addicted to it. When you’ve reached a plateau, you have to stir up your routine to move to the next level. But overtraining can be detrimental to the body.

If you’ve just started a workout routine and notice some soreness or changes in your appetite, weight or sleep schedule, this isn’t something to be too concerned over.

But, if you’ve been exercising for a while and have slowly increased the hours you spend training each week, keep an eye out for developing symptoms.

If you’re continually physically and mentally tired, and your muscle soreness doesn’t subside, you need to take a break.

Unless you’re a professional athlete, please, pace yourself when you work out.

Revathi Murugappan is a certified fitness trainer who tries to battle gravity and continues to dance, but longs for some bulk and flesh in the right places. She’s planning on bidding adieu to the stage this year with a final performance. The information provided is for educational and communication purposes only and it should not be construed as personal medical advice. Information published in this article is not intended to replace, supplant or augment a consultation with a health professional regarding the reader’s own medical care. The Star does not give any warranty on accuracy, completeness, functionality, usefulness or other assurances as to the content appearing in this column. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.