Resting measurements: HR, BP, body composition

Why baseline numbers matter

Resting measurements tell you where the client starts and whether anything concerning needs medical review before training.

Resting heart rate

Best taken first thing in the morning, before standing up, before caffeine. Adult range: 60-100 bpm. Athletic clients commonly 50-60. Below 40 with symptoms (dizziness, fainting) is bradycardia — medical referral. Above 100 at rest (tachycardia) — medical referral.

Track changes over time. A drop of 5-10 bpm over a few months of consistent training is a real adaptation signal.

Blood pressure

Sit quietly for 5 minutes. Cuff on bare arm at heart level. Take both arms first visit, then use the higher reading from now on.

Categories (per American Heart Association):

Normal: <120/<80
Elevated: 120-129 / <80
Stage 1 hypertension: 130-139 or 80-89
Stage 2 hypertension: ≥140 or ≥90
Crisis: >180 or >120 — stop, seek emergency care

Anyone reading Stage 2+ should be working with a physician before strenuous exercise. Trainers don't diagnose — but they don't ignore either.

Body composition methods

Skinfold calipers — cheap, decent accuracy (~3-5%) in trained hands. Inconsistent between testers. Best when same tester re-tests over time. Bioelectrical impedance (BIA) — handheld or scale-based. Variable accuracy (~3-8%) — heavily affected by hydration, food in stomach, recent exercise. Use only with consistent conditions. DEXA scan — gold standard for body composition. Accuracy ~1-2%. Requires a clinic. Expensive ($100-300/scan). Underwater weighing / BodPod — also high accuracy but rare. Tape measure — waist, hip, arm, thigh, chest. Cheapest. Tracks change well even if absolute numbers aren't precise.

What to actually do

Most clients don't need body fat percentages. They need:

Waist measurement (most predictive of metabolic risk)
Weight (track weekly, average over 4 weeks)
Photos (every 4 weeks, same lighting/clothes)
How clothes fit

If a client really wants a number, do skinfolds or BIA with consistent conditions — but explain the ±5% margin of error.

Red flags from initial measurements

BP ≥140/90
Resting HR <40 or >100 with symptoms
BMI ≥40
Sudden unexplained weight loss
Waist circumference >40 inches (men) or >35 inches (women) with other risk factors

All warrant physician clearance before high-intensity work.

TL;DR

Baseline HR and BP detect medical red flags. Use AHA blood pressure categories — refer at stage 2+. Body composition methods all have error — pick one and track change over time. Waist and weight changes matter more than precise body fat percentages.