Most people optimising their health have more data than they have ever had and no clearer sense of how they are actually doing.
The problem is not that wearables are useless. It is that they produce enormous volume with very little weighting, so a readiness score built from an unpublished algorithm ends up carrying the same apparent authority as a measure with forty years of outcome data behind it.
So here are four numbers that are simple, cheap to measure, and genuinely informative. Three of them you can measure this week with equipment you either own or can borrow.
Worth saying upfront. These are self-tracking measures for noticing trends over time. They are not diagnostic, they do not replace a conversation with your GP, and a single reading tells you far less than a direction of travel does.
1. Grip strength
The one that surprises people, because it sounds like it should only be about hands.
Grip strength is a proxy for total body strength and neuromuscular function, and it has an unusually strong relationship with long term health outcomes in the research literature. It correlates with all-cause mortality, cardiovascular outcomes and functional independence in later life more strongly than most things you can measure at home.
The interpretation is not that strong hands protect you. It is that grip strength is a clean, hard-to-fake window into overall muscular condition and neurological function, and both of those track with how well the whole system is holding up.
How to measure it. A hand dynamometer costs very little. Squeeze at maximum effort, three attempts per hand, take the best. Test under the same conditions each time, ideally not after a heavy training session.
What you are looking for. The trend. A single figure needs age and sex norms to interpret and those vary between reference sets. Your own number declining over a year is a clearer signal than any comparison to a table.
2. VO2 max
Maximum rate of oxygen use during intense effort, and the best single measure of cardiorespiratory fitness available.
It is worth understanding how large the effect here is. The difference in long term outcomes between the bottom fitness quintile and the ones above it is substantial, and moving out of the lowest group is associated with the largest benefit of any single step. The gains from being extremely fit rather than moderately fit are real but considerably smaller than the gain from not being unfit.
The practical consequence is that if your cardiorespiratory fitness is poor, that is almost certainly the highest value thing on your list, ahead of anything else you might be considering.
How to measure it. Laboratory testing is the gold standard and most people will not do it. Watch estimates are imprecise on absolute value but reasonable at tracking direction on the same device. A submaximal step test or a timed effort over a fixed distance both work as consistent proxies.
What you are looking for. Direction over six to twelve months. VO2 max declines with age by default, so holding it flat is a genuine win rather than a failure.
3. Waist to height ratio
Not weight. Not BMI. Waist circumference divided by height.
Weight conflates muscle, fat, fluid and everything else, which makes it close to useless for anyone training seriously. BMI has the same problem and adds nothing. Waist to height ratio is a better proxy for visceral fat, which is the fat distribution that actually carries metabolic consequence.
The commonly used guide is to keep your waist under half your height. It is crude, it is not universal across populations, and it still outperforms the scale for most people.
How to measure it. Tape measure, at the midpoint between the bottom rib and the top of the hip bone, at the end of a normal exhale. Same time of day, same conditions, ideally first thing in the morning.
What you are looking for. Monthly, not daily. This moves slowly and daily measurement produces noise you will misread as signal.
4. Resting heart rate
The one most people already have, sitting in an app they do not look at.
Resting heart rate reflects cardiovascular efficiency and autonomic balance. A lower resting rate generally indicates a heart moving more blood per beat and a nervous system not stuck in a stress state.
Its real value is as an early warning system. Resting heart rate tends to rise before you consciously notice you are run down, overtrained, fighting something off, or accumulating stress. A jump of five or more beats sustained over several days is usually your body flagging something before your subjective sense catches up.
How to measure it. Overnight or first thing on waking, before getting up. Any wearable does this adequately. Consistency of method matters more than device accuracy.
What you are looking for. Your normal range and deviations from it. The absolute number matters less than knowing what yours usually is.
Why these four
They cover different systems with minimal overlap. Grip strength reads muscular and neurological condition. VO2 max reads cardiorespiratory capacity. Waist to height reads metabolic risk. Resting heart rate reads recovery and autonomic state.
Together they give you a rough but genuine picture across four domains, using measures with real evidence behind them rather than proprietary scores.
They also share a useful property. None of them can be gamed in any way that does not involve actually improving. You cannot optimise your grip strength number without getting stronger. That is not true of most dashboard metrics, and people spend a surprising amount of effort improving scores rather than health.
How this connects to a protocol
Directly, in one specific way. These are your baseline.
The single most common frustration we hear at the end of a cycle is some version of "I think it helped but I am not certain." That uncertainty is almost always a measurement problem rather than a protocol problem. Without a baseline there is nothing to compare to, and memory is a poor instrument.
Take these four before you start anything. Take them again at the midpoint and at the end. It costs you twenty minutes across a twelve week cycle and it converts a vague impression into something you can actually reason about.
It also protects you from the opposite error, which is abandoning something that was working because the scale did not move.
The Reset takeaway
Grip strength, VO2 max, waist to height ratio and resting heart rate cover four different systems, have real evidence behind them, and cannot be improved without genuinely improving. Measure them before you change anything, then again at the midpoint and the end. If you want help working out which of these is your weakest link before building a protocol, message us on WhatsApp on +61488709561.
This article is for educational purposes only and does not constitute medical advice. Peptide protocols are prescription medicines in Australia and should always be designed and supervised by a qualified clinician.