Functional Capacity

The patient’s functional capacity has been shown to correlate well with maximal oxygen uptake on treadmill testing. Functional status or capacity is important to know because exercise capacity is a reliable predictor of future cardiac events. Functional capacity is usually expressed in metabolic equivalents (METs).

Greater than 7 METs of activity tolerance is considered excellent, whereas less than 4 METs is considered poor activity tolerance.

The Duke Activity Status Index suggests questions that correlate with MET levels. “For example, walking on level ground at about 4 miles per hour or carrying a bag of groceries up a flight of stairs expends approximately 4 METs of activity. Patients limited in their activity from noncardiac causes, such as severe osteoarthritis or general debility, are categorized as having a poor functional capacity because one cannot discern if significant cardiac conditions exist without the benefit of a functional study (noninvasive testing).” Cleveland Clinic

Easy MET Estimates

• 1 MET = Can take care of self, such as eat, dress, or use the toilet.
• 4 METs = Can walk up a flight of steps or a hill or walk on level ground at 3 to 4 mph.
• 4 and 10 METs = Can do heavy work around the house, such as scrubbing floors or lifting or moving heavy furniture, or climbing two flights of stairs (between)
• >10 METs = Can participate in strenuous sports such as swimming, singles tennis, football, basketball, and skiing.

* Being able to do 4 METs activities without symptoms is thought to be a good prognostic indicator.

See the table below for more.

Estimated Energy Requirement for Various Activities

MET = metabolic equivalent;

What is a Metabolic Equivalent Task (MET)?

Reference

https://www.ncbi.nlm.nih.gov/pubmed/2204507

http://onlinelibrary.wiley.com/doi/10.1002/clc.4960130809/epdf

Metabolic equivalents (METs)

http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/preventive-medicine/perioperative-evaluation/ (Last Accessed 4/24/2017)