Health Proxies You Can't Cheat

For exercise I focus on 2 things, education and meeting the patient where they are. I explain the metrics we will follow, what they mean and what they don't mean, cite the studies that give us confidence in using these specific metrics, and then explain how we can train to improve overall health. I then use the metrics such as VO2 max and grip strength as benchmarks we can use to follow improvements. I have patients starting at wildly different places when it comes to exercise. Once they are educated on the general types of exercise (weight resistance, zone 2, VO2 Max, balance and stability, NEAT) we can see where they need to put more time and focus. The entire time we are working on sustainability, making it a mostly pleasant and purposeful experience, and above all else NOT GETTING HURT! 

The key in this process is not mixing up these 'proxies' of health for actual health. A good example of a non-helpful health proxy in action would be a patient exclusively using hand squeezing devices to 'cheat' for the hand grip strength test. They are missing the entire point and improvement in this metric likely does not reflect a meaningful gain in overall health or longevity. 

Each metric however has its own nuances. For hand grip strength specifically, its value derives from if being highly correlated with overall strength. When it no longer becomes correlated with overall strength (such as in our pop-eye the sailor man biohacker) then the metric starts to lose its value. HOWEVER, it does not lose its incremental value completely. For starters while the value of increased grip strength is largely in its correlation with overall strength, having a strong grip even in isolation is important to helping to prevent falls. Being able to grab a railing or counter top and effectively arrest or at least greatly improve the outcome of a fall can be a game changer in older populations independent of how much they can squat. Additionally, to make the gains in hand grip strength, even in isolation, still requires adequate blood flow, solid neuronal innervation, optimal hormonal levels, and some modicum of cognitive and mental health for the focused discipline for training.

While handgrip strength might be on the easier end of the spectrum to cheat, other proxies for health are much more difficult to artificially change without it reflecting a meaningful improvement in health. VO2 max is a perfect example of this. You can't cheat for VO2 max. You can't wake up two weeks before testing and say, "you know what, I want to go from my 30 mL/kg/minute to 50 mL/kg/minute and I am going to do it in half a month". You just can't do it. It takes years of consistent work to get your VO2 max to improve. Thus VO2 max is an excellent integrator of tons of health behaviors (regular exercise, strong heart, healthy mitochondria, not smoking, functional kidneys, lower life stress, etc) and this is the underlying reason for why VO2 max is perhaps the best single metric we have at predicting healthspan and lifespan.

I am currently trying to capture the most predictive metrics of health (such as quad strength, farmer's carry, push ups in 1 minute, VO2 max, hand grip, lean muscle mass indices (ALMI/FFMI), 40 yard dash times, 5k times, etc) and trying to sort through them to answer exactly the question posed... What metrics can be cheated and what are too directly tied to health that they stand on their own.