ACSM Pre-Exercise Screening Algorithm

ACSM's current pre-participation screening (introduced in the 9th-edition update, formalized 2015, carried into the 10th/11th editions) replaced the old risk-factor-counting model. Instead it routes decisions through three inputs:

1. Current physical activity — performing planned, structured activity at moderate intensity ≥30 min, ≥3 days/wk for the last ≥3 months.
2. Presence of known cardiovascular, metabolic, or renal (CMR) disease, OR signs/symptoms suggestive of CMR disease (see signs-symptoms-cvd).
3. Desired exercise intensity — light, moderate, or vigorous (see intensity-classification).

Simplified logic:

• No known CMR disease and no signs/symptoms:
  • Currently active → may continue moderate or progress to vigorous without clearance.
  • Currently inactive → may begin light–moderate without clearance; medical clearance recommended before vigorous exercise.
• Known CMR disease but asymptomatic:
  • Currently active → clearance recommended before vigorous; may continue moderate.
  • Currently inactive → clearance recommended before moderate or vigorous.
• Any signs/symptoms suggestive of CMR disease (regardless of activity/known disease): discontinue any current exercise and seek medical clearance before (re)starting.

The intent is to remove unnecessary barriers: many apparently healthy and even some stable diseased-but-active people no longer require a physician visit just to begin moderate activity. Modeling on NHANES data suggested the algorithm reduced referrals by roughly 41% versus the old method. (referral-reduction figure)

• Three inputs: current activity status, known CMR disease or signs/symptoms, desired intensity.
• "Currently active" benchmark: moderate exercise ≥30 min, ≥3 days/wk, ≥3 months.
• Asymptomatic + no known disease + already active → no clearance needed even for vigorous.
• Inactive + no disease → clearance recommended only before vigorous.
• Any signs/symptoms of CMR disease → stop and obtain clearance.
• This algorithm replaced ACSM risk-factor counting (pre-2015).

• signs-symptoms-cvd — the symptom list that forces referral.
• par-q-plus — the self-screen counterpart.
• intensity-classification — defines light/moderate/vigorous used here.
• medical-clearance — the downstream step.
• hypertension / diabetes-exercise — common CMR diagnoses that feed the algorithm.