Ideally training should be prescribed individually, as should medication and lifestyle advice, according to each person's constitution, medical history,age needs and goals. And I say that as I was an NHS GP for 25years. Exercise and nutrition used to be a guessing game, with one size fits all, but these measurements mean that there is no guessing. You get to know what heart rate zones, that are individual to you, you should be working with to burn maximum fat, increase longevity and further increase fitness and strength levels. If you stick to the plan, which is in my case counterintuitive in that I am doing less work and seeing greater results. My overall fitness was good, but my fatburning efficiency wasn't. Working more on my zone 2 training with occasional short bursts of zone 4/5 training has actually improved my VO2 max. I also feel better in between. I am giving my body the chance to recover. This is a game changer for me. I am investing in my future quality of life and am the fittest I have ever felt at 55. Just doing the same high level workouts will not sustain you as you reach 40 and beyond. There is no judgment here. You can be tested whatever your weight, fitness and then get a bespoke program of nutritional guidance and exercise to upgrade your body to a more efficient mode.