A more appropriate target when using these self-monitoring technologies, and specifically to account for normal lifestyle activities, is probably around 1,000 minutes per week of moderate-to-vigorous intensity activity, according to a recent study. This is another estimation, but clearly, there is a huge difference between aiming for 150 instead of 1,000 minutes. And those keen to do the right amount of exercise for good health need to be aware of this discrepancy if they are using sophisticated technologies to assess their physical activity.
However this does not mean people need to do 1,000 minutes of “new” physical activity. It just means there is a lot of incidental activity that will be inevitably captured with these devices that needs to be taken into account.
A measured approach
A separate but equally important issue is that current recommendations focus on only moderate-to-vigorous intensity physical activity. But there are many other kinds of physical activity, such as sedentary time and overall energy expenditure. These other dimensions are demonstrably important for health, meaning there is a smorgasbord of physical activity options and choices rather than a one-size-fits-all prescription.
Feedback on any one of these dimensions alone, however they are measured, might be misleading if taken in isolation from the others. In the future, it will be important to ensure that people are provided with a more holistic picture of their physical activity across multiple dimensions. In this way they can form a more accurate view of the appropriateness of their behaviour and capitalise on all the different ways they can benefit from physical activity.
Hippocrates and Galen would no doubt be surprised that we are still grappling with basic issues around the amount of physical activity required for good health. For most people, it is probably safe to say that some kind of increase in physical activity will bring health benefits. Monitoring devices provide good and very useful information, but as far as using that information to work out exactly how much exercise we need and whether we are doing enough, we’re not at the finish line yet.