A clinical reference from Vital Capacity
The 7 tests are only the beginning.
ApoB, Lp(a), fasting insulin, OGTT with insulin, VO2 max, DEXA, and grip strength can show what routine care misses. The harder work is deciding what those numbers mean for one body, one family history, one training load, and one physician-owned plan.
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Vital Capacity
Clinical Reference
The 7 Tests
Routine Care
Usually Misses
The numbers matter. The physician judgment after the numbers matters more.
Andrew Irwin, MD, CSCS
Internal Medicine | Human Performance
What is inside
Seven measurements that change the clinical conversation.
01
ApoB
The particle count that drives atherosclerosis. Standard lipid panels can make the risk look smaller than it is.
02
Lp(a)
A genetic cardiovascular risk signal that changes the target for everything else you can modify.
03
Fasting insulin
The compensation signal that can rise years before glucose or A1C finally moves.
04
OGTT with insulin
A metabolic stress test that shows both glucose handling and the insulin cost of keeping glucose normal.
05
VO2 max
A direct measure of cardiorespiratory capacity and one of the strongest predictors of long-term survival.
06
DEXA body composition
Lean mass, visceral fat, and bone density in one scan. The scale cannot tell you any of this.
07
Grip strength
A fast proxy for total-body neuromuscular reserve, and a trend worth watching over time.
The reference and the responsibility
The reference can show you
What to measure, why the test matters, and what a concerning result may suggest.
A physician still has to decide
Whether to treat, repeat, refer, hold, screen relatives, adjust training, or take responsibility for a prescription.
Why this exists
The tests are accessible. The interpretation is where people get lost.
Most high-performing adults do not need another wellness list. They need to know which numbers meaningfully change risk, which numbers are noise, and when a physician should be on the hook for the next step.
01
Plain-language explanations of the seven tests and why routine care often misses them.
02
Targets and thresholds that help you understand when a result deserves attention.
03
A clinical frame for turning numbers into questions worth asking a physician.
04
The Vital Capacity newsletter, where the deeper judgment behind the numbers gets built in public.
About the author
Andrew Irwin, MD, CSCS
Internal medicine physician and Certified Strength and Conditioning Specialist with competitive training experience across Ironman, Hyrox, marathons, rugby, and hockey.
Vital Capacity is opening in phases for our founding patients. It integrates clinical medicine and exercise physiology — combining advanced labs, VO₂ max testing, DEXA body composition, strength and recovery metrics, with longitudinal physician oversight and medical follow-through that evolves as your body changes.
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Start with the numbers. Keep reading for the judgment.
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