Heart Rate Responses of Tetraplegics during Psycle Training
B. Mangold, D. Bruce, J. Priest, and R. Jennings
Tarleton State University, Tarleton Station, TX 76402
According to the National Spinal Cord Injury Association there are approximately 250,000 people in the United States who are spinal cord injured (SCI). The resulting immobility causes rapid degeneration of physiological functions and health. Furthermore, in tetraplegia, the heart rate response to exercise is limited due to the absence of sympathetic stimulus to the heart. The Psycle™Training Program was established by the Laboratory for Wellness and Motor Behavior (LWMB) to offer SCI individuals an opportunity to achieve health while mobilizing paralyzed parts of the body.
The program utilizes the Psycle™ (Intellifit®, Bedford, Texas), a specialized regenerative-drive, recumbent lower body ergometer. The Psycle™ has various adjustments to support and stabilize various degrees of hip, knee, and ankle mobility. It provides SCI individuals an opportunity to accomplish continual motion utilizing the paralyzed parts of the body without the use of motorization or functional electrical stimulus.
The Psycle™ is integrated with a 486 MHz computer to display and print results of each training session. Psycle™ Psoftware® (Intellifit®, Bedford, Texas) monitors heart rate (HR), revolutions per minute (RPM), total watts, average watts, work time, and percentage of points goal (a mathematical expression of a 30 minute cardiovascular workout at 75% of age-adjusted predicted maximum HR).
Four tetraplegics participated in 16 weeks of Psycle™Training. Prior to training, the subjects obtained an exercise prescription for Psycle™Training from a physician. Following admission to the program, subjects were assigned a personal trainer, who was selected from a pool of candidates who had completed exercise physiology, kinesiology, anatomy, and physiology. Individual training programs consisted of 5 minutes of warm-up followed by 15 to 45 minutes of continuous cycling at target heart-rates (THR) of 75% of age-predicted maximum.
SP(C5, ASIA Class C) trained at a mean HR of 131 ± 14 BPM. The mean workload was 35.4 ± 12.2 W, while peak work capacity improved 106% from 48 W to 99 W. BM (C6, ASIA Class B) trained at a mean HR of 93 ± 7 BPM and mean workload of 4.4 ± 1.1 W. JN (C6, ASIA Class A) trained at a mean of 110 ± 7 BPM and mean workload of 5.2 ± 1.2 W. ME (C5, ASIA Class A) who was additionally immobilized by heterotopic ossification of his hips, could not accomplish unassisted revolutions, but attained mean training HR of 86 ± 8 BPM and mean peak HR of 116 ± 10 BPM with trainer assistance. All subjects reported improved energy, decreased incidence of infection and muscle spasms, as well as decreased use of prescription drugs.
This research provides evidence that Psycle™Training may help individuals with tetraplegia to exercise at sufficient intensity to avoid much of the deconditioning associated with lack of exercise. Rehabilitation professional may consider implementation of Psycle™Training to benefit the health and fitness of individuals who have SCI.
*Psycle is a registered trademark of Intellifit Incorporated