Is Your Smart Watch Really Keeping You Healthy?

Dr Richard Alcock, a distinguished cardiologist, recently underwent a rigorous assessment to determine his maximal oxygen consumption, also known as VO2 max. This assessment is widely regarded as the gold standard indicator of cardiovascular fitness. During the assessment, his smart watch registered a reading of 56 mL/kg/min, which deviated approximately 10 per cent from the actual reading of 62.5 mL/kg/min.

The discrepancy in readings can be attributed to the fact that smart watches estimate metrics such as maximum oxygen consumption based on heart rate and speed, rather than directly measuring them like the gold standard physiology tests. While smart watches may offer a general overview of one’s health and fitness, they fall short in terms of scientific accuracy.

A study published in 2023 revealed that heart rate readings from smart watches can vary significantly based on exercise intensity and the movement of the wearer’s arms. Furthermore, another study highlighted that while wearables tend to overestimate sleep metrics due to their reliance on body movement, their accuracy is improving in newer models.

When it comes to tracking blood pressure, quality of sleep, and other metrics, smart watches still struggle to provide accurate readings. Although step count and distance measurement are relatively accurate, errors can arise when these readings are used to calculate other metrics, such as calorie burn.

Despite these limitations, over 36 per cent of Australians are in possession of a smart wrist wearable, indicating their popularity among consumers. While smart watches hold niche medical uses, such as detecting abnormal heartbeats, they are primarily marketed as general health and fitness trackers.

According to Dr Alcock, smart watches have the potential to motivate individuals to lead healthier lives by encouraging increased physical activity. Moreover, elite athletes have incorporated smart watches and fitness trackers into their training routines to enhance their performance. However, Professor Sophia Nimphius, an esteemed human performance expert, posits that these devices may be more beneficial for athletes in a controlled training environment, rather than for the average user.

Professor Nimphius cautions that the accuracy of wearables in measuring health and fitness metrics is often less than perfect. She advises users to focus on long-term trends in their data, rather than fixating on daily figures. She also emphasizes that these devices may not be effective for everyone as health and fitness tools, and that there is a psychological component to fully trusting the numbers displayed on these devices.

In addition to bearing in mind the limitations of smart watches and fitness trackers, users are also urged to be mindful of the manner in which their data is utilized by the companies behind these devices. Professor Nimphius underscores the potential privacy and ethical concerns related to the collection and utilization of fitness data by these companies, as it may divulge intimate details about individuals’ physiology without the same level of regulation as medical records.

In conclusion, while smart watches and fitness trackers offer convenient means to monitor various health and fitness metrics, consumers should carefully consider their limitations in accuracy, as well as the ethical considerations surrounding user data.