Body Temperature Responses in Spinal Cord Injured Individuals During Exercise in the Cold and Heat

Abstract

The aim of this study was to assess the effect of arm exercise on the heat balance in spinal cord-injured (SCI) individuals with complete lesions at ambient temperatures of 10 and 35 degrees C. Four SCI with a high lesion (> or = T6) (SCI-H), seven with a low lesion (< T6) (SCI-L), and ten able-bodied controls (AB) performed arm-cranking exercises at 40 % of the maximal power output for 45 min, once in 10 degrees C and once in 35 degrees C. Oxygen uptake, rectal temperature, and skin temperature (chest, upper arm, thigh, calf) were measured at rest and 15, 30, and 45 min after the onset of exercise. Metabolism, heat production, skin temperature, mean body temperature (a combination of rectal and skin temperature), and body heat content were calculated. Heart rate at 10 degrees C was 103 b/min in SCI-H, 120 in SCI-L and 112 in AB, while in 35 degrees C, heart rate was 112 b/min in SCI-H, 144 in SCI-L and 134 in AB. The increase in rectal temperature in 35 degrees C was larger in SCI-L (+ 0.07 degrees C) and SCI-H (+ 0.08 degrees C) than in AB (+ 0.06 degrees C). The decrease in mean body temperature at 10 degrees C was larger in SCI-H (33.0 +/- 0.68 degrees C) than in SCI-L (33.6 +/- 0.29 degrees C) and AB (34.5 +/- 0.31 degrees C). During exercise in 35 degrees C, mean body temperature increased in all three groups. The increase in body temperature in SCI-L was larger than in AB. During exercise in 10 degrees C, body heat content decreased in SCI-H (80.0 +/- 15.1 kJ) and SCI-L (89.2 +/- 9.1 kJ) but remained constant in AB (97.0 +/- 16.1 kJ). During exercise in 35 degrees C, body heat content increased in all three groups. The increase in body heat content after exercising in 35 degrees C was not significantly different between the three groups. In summary, mean body temperature and body heat content in the cold decreased in SCI, despite exercising. In the heat, mean body temperature and body heat content seems to increase more in SCI than in AB. We can conclude that SCI are at a greater risk for a disturbed heat balance during exercise in the cold and in the heat than AB. Both in the cold and in the heat, precautions should be taken even earlier and be more intensive for SCI than for AB.

Within-subject correlations between evening-related changes in body temperature and melatonin in the spinal cord injured

“…Another interesting observation is that the poikilothermic regulation of the lower limbs may relate to the somewhat cooler lower body skin temperature in the paraplegics and tetraplegics compared to able-bodied controls during the initial hours of the experiment. Anecdotal evidence indicates that SCI individuals often complain about ''cold legs'' and take precautions for this by wearing multiple layers on their lower limbs during the day (Boot et al, 2006;Price & Campbell, 1997). Taken together, our data suggest a role for melatonin to induce heat-loss during the evening hours in humans.…”

“…Given that upper and lower (i.e. above and below the lesion level) skin temperatures differ in SCI individuals (Boot et al, 2006;Price & Campbell, 1997), we also calculated mean (arithmetic) skin temperatures for upper (mean of sites 1-4) and lower body (mean of sites 5-8).…”

“…Individuals with a spinal cord injury (SCI) demonstrate an inability to thermo-regulate properly below the level of the lesion (Boot et al, 2006;Price & Campbell, 1997). Tetraplegic individuals have a disrupted neural pathway that passes through the cervical spinal cord, which is believed to be important for the secretion of melatonin (Claustrat et al, 2005).…”

Venous gas bubble formation and decompression risk after scuba diving in persons with chronic spinal cord injury and able-bodied controls

“…13 In paraplegia, cold exposure during diving may trigger muscle spasticity and a general reaction of autonomic nervous system with hypertension. In addition, SCI patients are at greater risk for disturbed heat balance during exercise in the cold than the able-bodied controls, 14 and this may adversely affect the outcome of decompression post dive. On the other hand, immersion was shown to be beneficial in alleviating spastic attacks and it has been recommended as a method to prevent spastic attacks.…”

The Determination of Changes in Body Heat Content during Exercise Using Calorimetry and Thermometry

“…Indeed, DH b is employed extensively as both a physiological criterion for maximal heat exposure (Blockley et al, 1954;Henane and Bittel, 1975;Holmer, 1989;Iampietro and Goldman, 1965;Kaufman, 1963), and as an analytical tool for assessing the thermal status of an individual for a wide range of subpopulations (Arngrimsson et al, 2004;Boot et al, 2006;Saunders et al, 2005;Webborn et al, 2005). In theory, the measurement of body heat exchange using simultaneous measures of total heat production and loss is the only method whereby DH b can be directly determined.…”