Newfoundland and Labrador Health Services is reporting an increase in cases of exercise-induced illness.

Rhabdomyolysis, or rhabdo, is caused by intense exercise.

Overexertion can cause muscle cells to leak into the bloodstream which can lead to kidney failure and can be fatal if not treated.

NL Health Services is reporting 20 cases of the condition in the eastern-urban zone since October 1.

Symptoms include severe muscle pain, weak or swollen muscles and urine that resembles the colour of steeped tea.

While physical activity is vital for health and well-being, any intense exercise should be done carefully with ample time set aside to rest afterwards.

Anyone with symptoms of rhabdo should proceed to the emergency room or urgent care clinic as soon as possible.