By Nurhafizah Tan
KUALA LUMPUR, Sept 21: Workouts such as spinning and CrossFit classes and high-intensity interval training (HIIT) are becoming increasingly popular among individuals aiming to improve their physical fitness. However, do these intensive activities cause more harm than good?
In the pursuit of the ideal body shape, some people may unknowingly push their bodies beyond their limits, risking serious conditions like rhabdomyolysis, where skeletal muscles break down rapidly and can lead to serious complications such as kidney damage.
Influencer Sofea Shra shared her experience of suffering from this condition, which led to her being hospitalised for five days after participating in just one spinning class. Her story has opened the eyes of many and drawn public attention to the dangers of overexerting oneself during exercise.
Commenting on this, fitness coach Kevin Zahri said it is important to understand one’s limits and capabilities to avoid exercising to the point of harming their health, particularly when engaging in high-intensity activities that test one’s endurance and fitness level.
“Every person’s fitness level is different. For someone participating (in an intensive session) for the first time, their fitness level may not be the same as that of their friends or other participants who have been attending for months. The person’s body has not attained the level of fitness to handle the demands of the exercise session.
“So, when they push themselves too hard to follow the instructor’s directions and keep up with the other participants, muscle breakdown occurs, and this breakdown produces by-products (such as the protein myoglobin), which can burden the kidneys,” he told Bernama.
Kevin, who has over 20 years of experience in the fitness field, suggested using a smartwatch to monitor heart rate readings during an exercise session, making it easier for the individuals concerned to control their pace.
“The maximum heart rate (HRmax) can be estimated using this formula: 220 minus your age. For example, if you’re 30 years old, your HRmax will be 220 – 30, that is, 190 bpm (beats per minute), and you need to ensure that your bpm doesn’t exceed 80 percent of this figure, which is 152 bpm. If it goes higher, you have to slow down, no matter what the instructor says.
“If you’re not using a smartwatch, a good indicator is that you should still be able to have a conversation and feel the strain of the exercise without being completely out of breath,” he said, also recommending the intake of electrolyte drinks for better hydration.
Fitness, he added, takes time to build, advising the public not to simply follow trends or be influenced by others but to exercise at their own pace and avoid letting their ego get in the way.
Meanwhile, consultant nephrologist and lecturer at Universiti Putra Malaysia Associate Prof Dr Nor Fadhlina Zakaria said rhabdomyolysis may be suspected in anyone who experiences muscle trauma due to injury or excessive exercising and if symptoms like muscle pain, fatigue and vomiting are present.
“However, it can also be identified at a later stage when kidney function deteriorates (with abnormal increases in blood creatinine and urea levels, and decreased urine output) or when there is a change in urine colour to reddish-brown,” she said.
She said a blood test to check the creatinine level is one of the ways to diagnose rhabdomyolysis. The condition may be confirmed if the reading exceeds 5,000 units per litre (U/L), whereas the normal range is below 200 U/L.
“In severe cases, patients may present with mental confusion or unstable heart rhythms which can be life-threatening,” she added.
Dr Nor Fadhlina, however, said cases of rhabdomyolysis resulting from fitness activities remain low as few people engage in intensive exercise sessions or marathons without adequate training and preparation.
She also said acute kidney damage, especially in cases of rhabdomyolysis, can be treated with the administration of large amounts of intravenous fluids such as isotonic saline, which can help preserve kidney function.
She added dialysis treatment might be necessary in severe cases although it is usually temporary, and that most patients can regain normal kidney function if treated promptly.
“The likelihood of these patients developing chronic kidney disease is still present, but with regular health monitoring, this can be avoided,” she said.
— BERNAMA