The aim of the study was to compare the exercise responses during maximum wheelchair propulsion on a motor driven treadmill (TM) and maximum arm cranking (AC) in a homogenous group of nine paraplegic men with clinically complete spinal cord lesions between T4 and T6. The test order for each ergometer was random and time between the two ergometer tests was 3-7 days. All experiments were conducted in an air conditioned environment (23 degrees C DB, 18 degrees C WB). The highest VO2 recorded during the final minute of arm cranking (1.65 +/- 0.14 l min-1) and wheelchair propulsion on the treadmill (1.72 +/- 0.10 l min-1) was not significantly different. There were no significant differences in heart rate during the final minute of arm cranking (177 +/- 3 b min-1), and wheelchair propulsion on a motor driven treadmill (177 +/- 4 b min-1), nor were there any significant differences in minute ventilation (STPD) between AC (52 +/- 6.6 l min-1) and TM (56.1 +/- 4.8 l min-1). The VCO2 l min-1 for AC (2.00 +/- 0.20 l min-1) and TM (2.00 +/- 0.12 l min-1) was also not significantly different. The present study found that, unlike previous studies, no significant differences in VO2 (l min-1, ml kg-1 min-1) VE (l min-1), VCO2 (l min-1) or heart rate (b min-1) were found between the two modes of ergometry during the last minute of incremental exercise to exhaustion in a homogenous group of T4-T6 paraplegic men.(ABSTRACT TRUNCATED AT 250 WORDS)