Aerobic fitness testing in patients with chronic low back pain: which test is best?

STUDY DESIGN This is a randomized comparison of three exercise tests in a sample of 30 patients with chronic low back pain. OBJECTIVES To determine, by comparing three exercise tests, which test yields the highest peak and predicted oxygen consumption in a sample of patients with chronic low back pain. SUMMARY OF BACKGROUND DATA Little is known about the level of aerobic fitness in patients with chronic low back pain, although many rehabilitation programs emphasize aerobic exercise as an important part of their therapy. Measurement of aerobic fitness levels in these patients remains a problem. In healthy individuals, the highest oxygen consumption values come from exercise tests that use the largest muscle groups. For a number of reasons, this may not be true in patients with chronic low back pain. METHODS In this study, 30 participants with chronic low back pain performed three symptom-limited maximal exercise tests: a treadmill, an upper extremity ergometer, and a bicycle ergometer. The tests were administered in randomized order. Heart rate was continuously monitored and oxygen consumption in terms of mL/kg/minute was measured by indirect calorimetry each 30 seconds. RESULTS The statistical difference among the tests was highly significant (P < 0.0001). The treadmill test yielded the highest peak and predicted oxygen consumption followed by the bicycle and the upper extremity ergometer test, respectively. CONCLUSIONS The treadmill test is the best test for measuring aerobic fitness levels in patients with chronic low back pain. It yielded the highest peak oxygen consumption compared with the other tests, coming closest to measuring maximal oxygen consumption.