Activity management based on 2-day cardiopulmonary exercise testing results

-brief description-

Theory
In "Conceptual model for physical therapist management of chronic fatigue syndrome/myalgic encephalomyelitis" by Todd E. Davenport, Staci R. Stevens, Mark J. VanNess, Christopher R. Snell, and Tamara Little, recommendations are divided into two categories, pacing self-management and therapeutic exercise.

Pacing self-management focuses on staying below the anaerobic threshold (AT) heart rate, as determined by a 2-day CPET. Strategies include wearing a heart rate monitor, frequent breaks including diaphragmatic breathing, alternate positions, and use of adaptive equipment, and keeping an activities log to further identify activities that induce PEM.

Therapeutic exercise is designed to prevent excessive use of the aerobic respiration system. They recommend starting with stretching and active range of motion exercises. When these are well tolerated without triggering PEM, the patient can move on to strength training: short duration, low intensity strengthening exercises with adequate rest intervals. Finally, patients can advance to short duration, low intensity interval training. Patients who can tolerate this can move on to short-duration aerobic interval training.

In all these stages, interval duration should be under 2 minutes, and the heart rate kept at 10% below the AT. The paper stresses caution and slow changes, as tolerated.

In the absence of 2-day CPET results, they suggest 3 methods of estimating the AT:
 * estimating the AT from V̇o2max measurements obtained during submaximal exercise testing;
 * the heart rate corresponding to Borg Rating of Perceived Exertion ratings of 13 to 15 during submaximal exercise testing may be used.
 * estimating the heart rate at AT by calculating 55% of the HR at the V̇o2max as a starting point, although specific establishment of the HR at the AT in this population requires additional research. In the general population, this is calculated by the formula (220-age) * 0.55.

Evidence

 * Case report on one-year follow-up of patient who was given a rehabilitation program after a 2-day CPET, and descriptive article by Cort Johnson on the study, providing additional information

Clinicians
Staci Stevens, at the Workwell Foundation

Betsy Keller at Ithaca College, NY, USA.

Costs & availability
2-day CPET testing is available at two locations:
 * Workwell Foundation (United States, CA)
 * Betsy Keller at Ithaca College (United States, NY) Cost is $2200. Because they are based in a college setting (not healthcare setting), they cannot process insurance (including Medicare or Medicaid), so the patient would need to work directly with their insurer about reimbursement. (private email)

Dr. Susan Levine has stated that she will not refer a patient for 2-day CPET testing unless a local physical therapist is willing to work with the patient to implement the exercise program. (private communication)

Learn more

 * Wikipedia