What is a performance physical?

A performance physical is an exam that measures how well your body works and where it is heading, rather than only screening for disease. It scores 4 functional domains - aerobic fitness (VO2 max), strength (grip), mobility (sit-to-rise, balance, gait speed), and body composition - and tracks each one over time. It runs alongside your standard physical, not instead of it.

How is this different from my regular annual physical?

A regular physical is built to catch and document disease: blood pressure, cholesterol, a metabolic panel, maybe an EKG. A performance physical adds capacity and trajectory, measuring what you can do and how that changes year to year. The standard exam answers whether you have a problem today; the performance physical tells you how well you are aging.

Which test predicts longevity the most?

VO2 max is the single strongest measurable predictor of how long and how well you live, with large mortality differences between the least-fit and most-fit groups. Muscle mass is close behind. Grip strength and the mobility tests are not quite as powerful on their own, but they are far faster and cheaper, which makes them excellent early-warning checks.

Can I do these tests at home?

Three of them, yes. Sit-to-rise, a 10-second one-leg stand, and your comfortable walking speed need no equipment. A hand dynamometer for grip strength costs about 30 dollars. VO2 max and body composition need either a wearable trend or a lab test. If you are older or deconditioned, do the balance and floor tests near a wall or with someone nearby.

Should I trust the VO2 max number on my Apple Watch or Garmin?

Trust the trend more than the single number. A 2025 study found the Apple Watch underestimated lab VO2 max by about 6 mL/kg/min, and accuracy varies by brand and fitness level. Where these devices shine is tracking the same person over time, so use your watch to see whether you are climbing or sliding, and get a formal test when a precise number will change your plan.

How often should I repeat the performance physical?

Most people do the full battery once a year, the same cadence as an annual exam. If you are actively changing your training or body composition, or recovering from an illness, we may recheck VO2 max, grip, or a DEXA scan every 3 to 6 months to confirm the plan is working.

I am out of shape and a little embarrassed. Is this still for me?

Yes, and that is exactly who benefits most. The point is to measure your starting line, not to judge it. The same exam fits a competitive athlete and a deconditioned beginner; only the numbers move. A low baseline is not a verdict, it is the first data point, and these measures improve with training at any age.

Does insurance cover any of this?

Because we practice evidence-based medicine, much of the surrounding workup, like advanced labs and many imaging studies, is often covered by your insurance rather than paid out of pocket. The simplest functional tests cost little or nothing on their own. We tell you up front what is covered, what is cash, and what is worth paying for.

Why is grip strength such a good proxy for whole-body health?

Grip strength tracks closely with total muscle strength and neuromuscular health, and it is sensitive to the early stages of frailty. It also reflects how well you would tolerate and recover from a serious illness or surgery. Because it is fast, cheap, and repeatable, it gives us a sensitive trend line for overall strength without a full strength workup.

What does the sit-to-rise test actually measure?

Sit-to-rise blends lower-body and core strength, balance, flexibility, and coordination into a single score. That combination is why it tracks so well with mortality and independence: it captures whether your strength and mobility work together in the kind of compound movement daily life demands. A rising score over time usually means your training is reaching the things that keep you autonomous.

How quickly do these numbers improve once I start training?

Most people see meaningful change within 8 to 12 weeks of consistent training. VO2 max often improves 10 to 20% in the first few months for beginners, grip and sit-to-rise scores climb as strength builds, and body composition shifts over a few months with resistance training and adequate protein. The early wins tend to be the fastest, which makes repeat testing motivating.

How does the performance physical fit with the rest of preventive care?

It sits inside the same approach we bring to preventive cardiology and metabolic health. Functional capacity, advanced lipids, blood pressure, and metabolic markers each tell part of the story, and together they show where to act. You can see how we frame the bigger picture in healthspan versus lifespan and our Medicine 3.0 approach.

What is a performance physical?

A performance physical is an exam that measures how well your body works and where it is heading, rather than only screening for disease. It scores 4 functional domains - aerobic fitness (VO2 max), strength (grip), mobility (sit-to-rise, balance, gait speed), and body composition - and tracks each one over time. It runs alongside your standard physical, not instead of it.

How is this different from my regular annual physical?

A regular physical is built to catch and document disease: blood pressure, cholesterol, a metabolic panel, maybe an EKG. A performance physical adds capacity and trajectory, measuring what you can do and how that changes year to year. The standard exam answers whether you have a problem today; the performance physical tells you how well you are aging.

Which test predicts longevity the most?

VO2 max is the single strongest measurable predictor of how long and how well you live, with large mortality differences between the least-fit and most-fit groups. Muscle mass is close behind. Grip strength and the mobility tests are not quite as powerful on their own, but they are far faster and cheaper, which makes them excellent early-warning checks.

Can I do these tests at home?

Three of them, yes. Sit-to-rise, a 10-second one-leg stand, and your comfortable walking speed need no equipment. A hand dynamometer for grip strength costs about 30 dollars. VO2 max and body composition need either a wearable trend or a lab test. If you are older or deconditioned, do the balance and floor tests near a wall or with someone nearby.

Should I trust the VO2 max number on my Apple Watch or Garmin?

Trust the trend more than the single number. A 2025 study found the Apple Watch underestimated lab VO2 max by about 6 mL/kg/min, and accuracy varies by brand and fitness level. Where these devices shine is tracking the same person over time, so use your watch to see whether you are climbing or sliding, and get a formal test when a precise number will change your plan.

How often should I repeat the performance physical?

Most people do the full battery once a year, the same cadence as an annual exam. If you are actively changing your training or body composition, or recovering from an illness, we may recheck VO2 max, grip, or a DEXA scan every 3 to 6 months to confirm the plan is working.

I am out of shape and a little embarrassed. Is this still for me?

Yes, and that is exactly who benefits most. The point is to measure your starting line, not to judge it. The same exam fits a competitive athlete and a deconditioned beginner; only the numbers move. A low baseline is not a verdict, it is the first data point, and these measures improve with training at any age.

Does insurance cover any of this?

Because we practice evidence-based medicine, much of the surrounding workup, like advanced labs and many imaging studies, is often covered by your insurance rather than paid out of pocket. The simplest functional tests cost little or nothing on their own. We tell you up front what is covered, what is cash, and what is worth paying for.

Why is grip strength such a good proxy for whole-body health?

Grip strength tracks closely with total muscle strength and neuromuscular health, and it is sensitive to the early stages of frailty. It also reflects how well you would tolerate and recover from a serious illness or surgery. Because it is fast, cheap, and repeatable, it gives us a sensitive trend line for overall strength without a full strength workup.

What does the sit-to-rise test actually measure?

Sit-to-rise blends lower-body and core strength, balance, flexibility, and coordination into a single score. That combination is why it tracks so well with mortality and independence: it captures whether your strength and mobility work together in the kind of compound movement daily life demands. A rising score over time usually means your training is reaching the things that keep you autonomous.

How quickly do these numbers improve once I start training?

Most people see meaningful change within 8 to 12 weeks of consistent training. VO2 max often improves 10 to 20% in the first few months for beginners, grip and sit-to-rise scores climb as strength builds, and body composition shifts over a few months with resistance training and adequate protein. The early wins tend to be the fastest, which makes repeat testing motivating.

How does the performance physical fit with the rest of preventive care?

It sits inside the same approach we bring to preventive cardiology and metabolic health. Functional capacity, advanced lipids, blood pressure, and metabolic markers each tell part of the story, and together they show where to act. You can see how we frame the bigger picture in healthspan versus lifespan and our Medicine 3.0 approach.

Performance Physical Philadelphia: 4 Tests That Predict How You Age

TL;DR · 30-second take

A standard physical looks for disease. It tells you very little about how well you are aging. 4 functional measures predict that better: VO2 max (your aerobic fitness), grip strength, mobility (getting off the floor, balancing on one leg, walking speed), and body composition. Each is cheap to measure, easy to track over time, and trainable at any age. The same exam fits a 35-year-old runner and a deconditioned 60-year-old; only the numbers move.

Why your annual physical misses how you're aging
The performance physical: 4 measures that predict how you'll age
VO2 max: your aerobic engine
Grip strength: the 2-minute test that predicts a lot
Can you get off the floor? The mobility battery
Body composition: the muscle you bank for later
Your smartwatch and VO2 max: track the trend, not the number
What this costs, and what's worth paying for
Common Questions
Deep Questions

Why your annual physical misses how you're aging

Your yearly physical is built to catch disease and satisfy a billing code. Blood pressure, cholesterol, a basic metabolic panel, maybe an EKG. That work matters, and we do all of it. But it mostly answers whether you have a disease today. It says little about how well your body is working, or where it is heading over the next 30 years.

Longevity medicine adds a second exam. Call it the performance physical. Instead of screening only for illness, it measures capacity and trajectory: how much your heart and lungs can do, how strong you are, how well you move, and what your body is made of. Each of these has been studied against the outcomes that matter most, like death, disability, and losing your independence. And unlike your age or your genes, every one of them improves with training.

A lot of patients land in my office after years of being told their labs are normal while they slowly lose a step. Normal labs are not the finish line. How you function is.

The performance physical: 4 measures that predict how you'll age

4 functional measures carry most of the signal. They are quick, most of them need almost no equipment, and you can track each one against yourself over time.

Measure	What it predicts	How we check it
VO2 max	Cardiorespiratory fitness; one of the strongest predictors of lifespan and brain health	Wearable estimate for the trend; a lab CPET when the result will change the plan
Grip strength	Whole-body strength, frailty risk, recovery from illness	Hand dynamometer, both hands, about 2 minutes
Mobility	Whether strength and fitness translate into everyday independence	Sit-to-rise, a 10-second one-leg stand, comfortable walking speed
Body composition	Muscle you can defend with age, and the fat wrapped around your organs	DEXA scan, plus a look at protein intake

Here is the idea that ties them together. The work that keeps a competitive athlete in the game at 40 is the same work that keeps a sedentary person independent at 80. Same assessments, same levers, different starting dose. The performance physical fits a marathoner and a deconditioned 60-year-old equally well. Only the numbers move.

Two of these, VO2 max and muscle, are the headline predictors of how long and how well you live, and I go deep on training them in VO2 max, muscle mass, and the centenarian decathlon. The other two, grip and mobility, are the fastest and cheapest early-warning checks you can run. Together they give you a baseline a standard physical misses.

VO2 max: your aerobic engine

VO2 max is the most oxygen your body can take in and use during hard effort. It reflects the heart, lungs, blood, and muscle all working together, which is part of why it predicts death better than almost anything else in the chart.

In a study of 122,007 patients undergoing treadmill testing, Mandsager and colleagues found fitness inversely tied to mortality with no upper limit of benefit. People in the elite-fitness group had roughly an 80% lower risk of death than the least-fit group. That gap rivaled or exceeded the risk carried by smoking, diabetes, and coronary disease. Few things we can measure move the needle that far.

The part most people miss is that VO2 max is not a fixed trait you inherit and keep. It responds to training at any age, which makes it a treatment target, not just a risk score. We treat it like blood pressure: measure it, prescribe a dose of training, measure again, adjust. I walk through the Zone 2 and Zone 5 prescription on the VO2 max training page, and when a patient wants a precise baseline, we coordinate a formal VO2 max test in Philadelphia.

Grip strength: the 2-minute test that predicts a lot

Grip strength is the cheapest powerful test you own. A hand dynamometer takes about 2 minutes, and the number it gives you stands in for whole-body strength, neuromuscular health, and how well you would weather a serious illness.

The data here is hard to argue with. In the PURE study, which followed nearly 140,000 adults across 17 countries, each 5 kg drop in grip strength was associated with about a 16% higher risk of death. Newer NHANES analyses point the same way, with the weakest adults facing roughly double the mortality risk of the strongest.

Grip is not only a readout; it moves when you train it. Resistance training is the active ingredient, and the dynamometer lets us prove the program is working from one visit to the next. I cover how we use it as a quick function check in grip strength as a longevity marker.

Can you get off the floor? The mobility battery

Strength and fitness only help if they translate into moving through your day. Three quick mobility checks tell you whether they do, and you can run all of them in under 10 minutes with no equipment. These are the tests almost no standard physical includes, and the outcomes data behind them is striking.

Sit-to-rise. You sit down on the floor and stand back up, scoring out of 10 based on how much support you need from a hand, a knee, or a forearm. Brito and colleagues found that adults aged 51 to 80 who scored below 8 had 2 to 5 times the mortality risk over the following 6 years, and each 1-point improvement was linked to a 21% lower risk of death. It looks like a party trick. It is one of the better functional screens we have.

The 10-second one-leg stand. Stand on one leg for 10 seconds. A 2022 cohort study in the British Journal of Sports Medicine found that people who could not hold the stance had about an 84% higher risk of death over a median of roughly 7 years, independent of age, sex, body weight, and existing conditions. Balance is not a vanity metric; it is a window into your nervous system and your fall risk.

Walking speed. Comfortable gait speed is one of the most studied predictors of aging outcomes. Walking slower than 0.8 meters per second flags elevated risk of disability, hospitalization, and earlier death, while a pace above 1.0 meters per second is a marker of healthy aging. We can measure it in a hallway in under a minute.

In Philadelphia, the everyday version of these tests is everywhere: carrying groceries up a narrow Fishtown rowhome staircase, the climb up from the El at Girard, getting down to play on the floor with a grandkid and back up again. The floor battery just measures, on purpose, what your neighborhood already asks of you.

A practical note: if you are older, deconditioned, or have a history of falls, do the balance and floor tests near a wall or a sturdy chair, or with someone spotting you. The point is to measure your starting line safely, not to take a fall proving it.

Body composition: the muscle you bank for later

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The scale cannot tell you the two things that matter most: how much muscle you carry, and how much fat is wrapped around your organs. A DEXA scan can. We track appendicular lean mass (the muscle on your arms and legs) and visceral fat, and we watch both over time. You can read more about why we favor this over weight on the body composition page, and we coordinate scans through our DEXA service in Philadelphia.

Muscle is the tissue you spend decades either building or quietly losing. Strength fails without fuel, so we anchor nutrition on protein, around 1.6 grams per kilogram of body weight for anyone building or defending muscle. Protein works best next to training, not instead of it. Train first, then feed the training.

How much training. A 2026 analysis in the British Journal of Sports Medicine followed 147,000 adults for up to 30 years and found a sweet spot: 90 to 120 minutes of strength training per week was associated with a 13% lower risk of death overall, a 19% lower risk of cardiovascular death, and a 27% lower risk of neurological death. The benefit flattened above 120 minutes. So if a patient asks how much lifting is enough, 90 minutes a week is a defensible floor, and the dynamometer and DEXA tell you whether it is working.

This matters more, not less, for patients on GLP-1 medications. Rapid weight loss strips muscle along with fat, so the target is not the number on the scale; it is protecting functional tissue. We track lean mass with body composition rather than weight alone, and we pair the medication with resistance training and enough protein to defend muscle quality.

Your smartwatch and VO2 max: track the trend, not the number

Your watch already estimates your VO2 max, and patients ask me constantly whether to trust it. Here is the honest answer.

A 2025 validation study in PLOS One put the Apple Watch up against the gold-standard lab test in 30 adults. On average, the watch underestimated VO2 max by about 6 mL/kg/min, with a mean absolute percentage error of 13.3%. A 2025 systematic review in Frontiers found that Garmin estimates from a short submaximal run often land within 10% of lab values, but accuracy varies by brand, by context, and by how fit you are.

So the single reading on your wrist can be off, sometimes by a lot. What these devices do well is track the same person over time. The trend matters more than the number on any given day. Use the wearable to see whether you are climbing or sliding month over month, and order a formal test only when the result will change what you do. That turns wrist data from a vanity score into a useful signal, as long as the trend, not the number, is driving the decision.

This is where I land on a lot of longevity tech. Some of it is woo-woo, and some of it is careful, evidence-based work. My job is to bring in the part that gives you results and to be honest about the part that does not.

What this costs, and what's worth paying for

The most predictive tests here cost almost nothing. Sit-to-rise, the one-leg stand, and walking speed are free. A hand dynamometer runs about 30 dollars. You do not need a 150,000-dollar recovery chamber or a boutique biological-age kit to know how you are aging; you need a few simple measurements and the discipline to repeat them.

Worth paying for, when the result will change your plan: a formal VO2 max test to set a precise baseline and find your training zones, and a DEXA scan to see muscle and visceral fat the scale hides. Because we practice evidence-based medicine, much of the surrounding workup, like advanced labs and imaging, is often covered by your insurance rather than paid out of pocket beyond your membership. The performance physical fits inside the same preventive approach we bring to cardiology and metabolic health: stop guessing and start measuring.

Guidance from the Clinic

"Most physicals are built to find disease and close a billing code. That is necessary work, and we do it. But it tells you almost nothing about whether you will be able to carry groceries up your stairs at 80. I would rather measure what your body can actually do, watch the trend over years, and train it. Build the baseline once, then run it every year. The same exam serves the masters athlete and the deconditioned 60-year-old. Only the numbers move."

Actionable Steps in Philly

Build your baseline once, then run it every year.

Know your VO2 max: track the trend on your watch, and get a formal test when you want a precise number and your training zones.
Test your grip: a 30-dollar hand dynamometer, both hands, about 2 minutes. Flag the lowest range for your age.
Run the floor battery: sit-to-rise, a 10-second one-leg stand, and your comfortable walking speed. Do the balance work near a wall if you are deconditioned.
Get a DEXA scan: muscle and visceral fat, not the bathroom scale. Repeat every 6 to 12 months if you are changing your body composition.
Train the gap: 90 to 120 minutes of strength work per week, Zone 2 cardio, and protein around 1.6 g/kg to defend muscle.

We fold your Apple Watch, Whoop, or Oura data into the plan, so we can see how your training time is actually distributed and where to push next.

Start with a short intake, your story in your own words

Key Takeaways

A standard physical screens for disease. A performance physical measures how well you are aging. They answer different questions, and you want both.
Four measures carry most of the signal: VO2 max, grip strength, mobility, and body composition. Each is measurable, trackable, and trainable.
The cheapest tests predict a lot. Sit-to-rise, a 10-second one-leg stand, and walking speed are free and tied to hard outcomes.
Track the trend, not the number. Wearable VO2 max can be off on any given day, but the direction over months is useful.
The same exam fits everyone. Marathoner or deconditioned 60-year-old, only the numbers move.

Scientific References

Mandsager K, et al. Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing. JAMA Network Open. 2018;1(6):e183605.
Leong DP, et al. Prognostic value of grip strength: findings from the Prospective Urban Rural Epidemiology (PURE) study. The Lancet. 2015;386(9990):266-273.
Brito LBB, et al. Ability to sit and rise from the floor as a predictor of all-cause mortality. European Journal of Preventive Cardiology. 2014;21(7):892-898.
Araujo CG, et al. Successful 10-second one-legged stance performance predicts survival in middle-aged and older individuals. British Journal of Sports Medicine. 2022;56(17):975-980.
Studenski S, et al. Gait speed and survival in older adults. JAMA. 2011;305(1):50-58.
Zhang Y, Lee DH, et al. Long-term resistance training with all-cause and cause-specific mortality: dose-response and joint associations with aerobic activity. British Journal of Sports Medicine. 2026.
Lambe R, et al. Investigating the accuracy of Apple Watch VO2 max measurements: a validation study. PLOS One. 2025;20(5):e0323741.
Železnik Mežan L. Accuracy of wearables for determining the maximal oxygen uptake and lactate threshold: a qualitative systematic review. Frontiers in Sports and Active Living. 2025;7:1707991.

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Frequently Asked Questions

Common Questions

Deep-Dive Questions

VO2 max integrates the function of several systems at once: the heart's pumping capacity, the lungs' gas exchange, the blood's oxygen-carrying ability, and the muscle's ability to use that oxygen. A high number means all of those are working well together, while a low number often reflects an early problem in one of them. That is why moving from low to above-average fitness is tied to such large reductions in risk.

Balance is highly trainable. It depends on your nervous system, your ankle and hip strength, and your vision working together, and all three respond to practice. Single-leg work, controlled strength training, and specific balance drills improve the 10-second one-leg stand for most people, which matters because better balance lowers fall risk, and falls are a leading cause of lost independence with age.

GLP-1 medications drive rapid weight loss that includes muscle along with fat, so the scale alone can hide a worrying loss of functional tissue. We track lean mass with a DEXA scan rather than body weight, and we pair the medication with resistance training and protein around 1.6 g/kg to defend muscle quality. The goal is fat loss with muscle preserved, which body composition confirms and the scale cannot.

BMI and body weight cannot distinguish muscle from fat, or tell you where fat sits. Two people at the same weight can have very different amounts of muscle and very different visceral fat, which is the inflammatory fat around the organs that drives metabolic risk. A DEXA scan separates these, so we can protect muscle and target visceral fat directly instead of chasing a single number on the scale.

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