<b>Cardiac autonomic profile in cervical spinal cord injury subjects practitioners of the physical exercise

Abstract

The aim was investigate the time-course of cardiac autonomic response in men with incomplete cervical spinal cord injury (SCI) practitioners or not of physical exercise. Twenty men were separated into three groups: control group without SCI (CON; 28.3 ± 4.5 yrs; 178.4 ± 6.5 cm; 82.1 ± 6.8 kg; n=8), regularly engaged in strength training and low aerobic training; exercise group with cervical SCI (EG, 32.3 ± 4.5 yrs, 175.1 ± 5.3 cm, 73.6 ± 9.6 Kg; n=8) that practiced wheelchair rugby and sedentary group with cervical SCI (SG, 30.8 ± 5.3 yrs, 173.4 ± 10.1 cm, 69.7 ± 7.1 Kg; n=4) who did not practice physical exercise. Heart rate variability variables were calculated from ECG, in rest. CON showed high values compared to EG and SG of: standard deviation of R-R intervals (SDNN), proportion of adjacent R-R intervals differing by more than 50 ms, number of interval differences of successive NN intervals greater than 50 ms, root mean square of successive differences and the high-frequency spectral power. SDNN was significantly lower in EG compared to CON. changes in cardiac autonomic function could be noted in subjects with cervical SCI regularly engaged in an exercise program.

Altered heart rate variability and pulse-wave velocity after spinal cord injury

“…In the present and previous studies, HRV alterations (particularly lower SDNN) were predictive of progressive coronary artery disease in people with SCI and were found more frequently in those with a sedentary lifestyle and without regular physical exercise[ 14 ]. Physical exercise after SCI is shown to increase sympathetic activity and may help minimize the risk of cardiac arrhythmias and prevent sudden cardiac death in those with cervical SCI[ 28 ]. Fatigue is also associated with altered HRV parameters and greater risk of cardiovascular sequelae after SCI; appropriate levels of exercise as well as sufficient sleep and dietary measures are recommended as anti-fatigue and anti–cardiovascular-risk strategies[ 16 ].…”

“…The present pilot study found that comprehensive evaluation of HRV and vascular age indicators addresses the full spectrum of poor AE, SDNN, and RMSSD in those with SCI. Studies have shown that physical activity, painting, respiratory training, music therapy, and nature therapy have the potential to reduce stress and improve HRV-related disorders and blood vessel structure[ 28 , 31 - 34 ]. Changes in the autonomic system, for example, are readily observed in response to physical exercise in individuals with SCI.…”

“…Changes in the autonomic system, for example, are readily observed in response to physical exercise in individuals with SCI. Adjustments occur in the cardiac autonomic system as a result of exercise-induced remodeling of damaged axons, which increases sympathetic activity and may help to minimize risk of arrhythmia or sudden cardiac death in those with cervical SCI[ 28 ]. Kyriakides et al [ 31 ] examined the effects of regular physical workouts (four-hour sessions once a week for three months) on reducing the HRV of people with SCI, reporting that all HRV metrics improved in SCI patients who engaged in this exercise program.…”