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New Findings: What is the central question of this study? To what extent are the mechanical-ventilatory responses to upper-body exercise influenced by task-specific locomotor mechanics? What is the main finding and its importance? When compared with lower-body exercise performed at similar ventilations, upper-body exercise was characterized by tidal volume constraint, dynamic lung hyperinflation and an increased propensity towards neuromechanical uncoupling of the respiratory system. Importantly, these responses were independent of respiratory dysfunction and flow limitation. Thus, the mechanical ventilatory responses to upper-body exercise are attributable, in part, to task-specific locomotor mechanics (i.e. non-respiratory loading of the thorax)., Abstract: The aim of this study was to determine the extent to which the mechanical ventilatory responses to upper-body exercise are influenced by task-specific locomotor mechanics. Eight healthy men (mean ± SD: age, 24 ± 5 years; mass, 74 ± 11 kg; and stature, 1.79 ± 0.07 m) completed two maximal exercise tests, on separate days, comprising 4 min stepwise increments of 15 W during upper-body exercise (arm-cranking) or 30 W during lower-body exercise (leg-cycling). The tests were repeated at work rates calculated to elicit 20, 40, 60, 80 and 100% of the peak ventilation achieved during arm-cranking ( V ̇ E , UBE ). Exercise measures included pulmonary ventilation and gas exchange, oesophageal pressure-derived indices of respiratory mechanics, operating lung volumes and expiratory flow limitation. Subjects exhibited normal resting pulmonary function. Arm-crank exercise elicited significantly lower peak values for work rate, O 2 uptake, CO 2 output, minute ventilation and tidal volume (p < 0.05). At matched ventilations, arm-crank exercise restricted tidal volume expansion relative to leg-cycling exercise at 60% V ̇ E , UBE (1.74 ± 0.61 versus 2.27 ± 0.68 l, p < 0.001), 80% V ̇ E , UBE (2.07 ± 0.70 versus 2.52 ± 0.67 l, p < 0.001) and 100% V ̇ E , UBE (1.97 ± 0.85 versus 2.55 ± 0.72 l, p = 0.002). Despite minimal evidence of expiratory flow limitation, expiratory reserve volume was significantly higher during arm-cranking versus leg-cycling exercise at 100% V ̇ E , UBE (39 ± 8 versus 29 ± 8% of vital capacity, p = 0.002). At any given ventilation, arm-cranking elicited greater inspiratory effort (oesophageal pressure) relative to thoracic displacement (tidal volume). Arm-cranking exercise is sufficient to provoke respiratory mechanical derangements (restricted tidal volume expansion, dynamic hyperinflation and neuromechanical uncoupling) in subjects with normal pulmonary function and expiratory flow reserve. These responses are likely to be attributable to task-specific locomotor mechanics (i.e. non-respiratory loading of the thorax)., (© 2019 The Authors. Experimental Physiology Published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Purpose: Diaphragm and abdominal muscles are susceptible to contractile fatigue in response to high-intensity, whole-body exercise. This study assessed whether the ventilatory and mechanical loads imposed by high-intensity, upper-body exercise would be sufficient to elicit respiratory muscle fatigue., Methods: Seven healthy men (mean ± SD; age = 24 ± 4 yr, peak O2 uptake [V˙O2peak] = 31.9 ± 5.3 mL·kg·min) performed asynchronous arm-crank exercise to exhaustion at work rates equivalent to 30% (heavy) and 60% (severe) of the difference between gas exchange threshold and V˙O2peak. Contractile fatigue of the diaphragm and abdominal muscles was assessed by measuring pre- to postexercise changes in potentiated transdiaphragmatic and gastric twitch pressures (Pdi,tw and Pga,tw) evoked by supramaximal magnetic stimulation of the cervical and thoracic nerves, respectively., Results: Exercise time was 24.5 ± 5.8 min for heavy exercise and 9.8 ± 1.8 min for severe exercise. Ventilation over the final minute of heavy exercise was 73 ± 20 L·min (39% ± 11% maximum voluntary ventilation) and 99 ± 19 L·min (53% ± 11% maximum voluntary ventilation) for severe exercise. Mean Pdi,tw did not differ pre- to postexercise at either intensity (P > 0.05). Immediately (5-15 min) after severe exercise, mean Pga,tw was significantly lower than pre-exercise values (41 ± 13 vs 53 ± 15 cm H2O, P < 0.05), with the difference no longer significant after 25-35 min. Abdominal muscle fatigue (defined as ≥15% reduction in Pga,tw) occurred in 1/7 subjects after heavy exercise and 5/7 subjects after severe exercise., Conclusions: High-intensity, upper-body exercise elicits significant abdominal, but not diaphragm, muscle fatigue in healthy men. The increased magnitude and prevalence of fatigue during severe-intensity exercise is likely due to additional (nonrespiratory) loading of the thorax.

Introduction: Asynchronous arm-cranking performed at high cadences elicits greater cardiorespiratory responses compared to low cadences. This has been attributed to increased postural demand and locomotor-respiratory coupling (LRC), and yet, this has not been empirically tested. This study aimed to assess the effects of cadence on cardiorespiratory responses and LRC during upper-body exercise., Methods: Eight recreationally-active men performed arm-cranking exercise at moderate and severe intensities that were separated by 10 min of rest. At each intensity, participants exercised for 4 min at each of three cadences (50, 70, and 90 rev min -1 ) in a random order, with 4 min rest-periods applied in-between cadences. Exercise measures included LRC via whole- and half-integer ratios, cardiorespiratory function, perceptions of effort (RPE and dyspnoea), and diaphragm EMG using an oesophageal catheter., Results: The prevalence of LRC during moderate exercise was highest at 70 vs. 50 rev min -1 (27 ± 10 vs. 13 ± 9%, p = 0.000) and during severe exercise at 90 vs. 50 rev min -1 (24 ± 7 vs. 18 ± 5%, p = 0.034), with a shorter inspiratory time and higher mean inspiratory flow (p < 0.05) at higher cadences. During moderate exercise, [Formula: see text] and f C were higher at 90 rev min -1 (p < 0.05) relative to 70 and 50 rev min -1 ([Formula: see text] 1.19 ± 0.25 vs. 1.05 ± 0.21 vs. 0.97 ± 0.24 L min -1 ; f C 116 ± 11 vs. 101 ± 13 vs. 101 ± 12 b min -1 ), with concomitantly elevated dyspnoea. There were no discernible cadence-mediated effects on diaphragm EMG., Conclusion: Participants engage in LRC to a greater extent at moderate-high cadences which, in turn, increase respiratory airflow. Cadence rate should be carefully considered when designing aerobic training programmes involving the upper-limbs.

We asked whether specific inspiratory muscle training (IMT) improves respiratory structure and function and peak exercise responses in highly trained athletes with cervical spinal cord injury (SCI). Ten Paralympic wheelchair rugby players with motor-complete SCI (C5-C7) were paired by functional classification then randomly assigned to an IMT or placebo group. Diaphragm thickness (B-mode ultrasonography), respiratory function [spirometry and maximum static inspiratory (PI ,max ) and expiratory (PE ,max ) pressures], chronic activity-related dyspnea (Baseline and Transition Dyspnea Indices), and physiological responses to incremental arm-crank exercise were assessed before and after 6 weeks of pressure threshold IMT or sham bronchodilator treatment. Compared to placebo, the IMT group showed significant increases in diaphragm thickness (P = 0.001) and PI ,max (P = 0.016). There was a significant increase in tidal volume at peak exercise in IMT vs placebo (P = 0.048) and a strong trend toward an increase in peak work rate (P = 0.081, partial eta-squared = 0.33) and peak oxygen uptake (P = 0.077, partial eta-squared = 0.34). No other indices changed post-intervention. In conclusion, IMT resulted in significant diaphragmatic hypertrophy and increased inspiratory muscle strength in highly trained athletes with cervical SCI. The strong trend, with large observed effect, toward an increase in peak aerobic performance suggests IMT may provide a useful adjunct to training in this population., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

We asked whether elastic binding of the abdomen influences respiratory mechanics during wheelchair propulsion in athletes with cervical spinal cord injury (SCI). Eight Paralympic wheelchair rugby players with motor-complete SCI (C5-C7) performed submaximal and maximal incremental exercise tests on a treadmill, both with and without abdominal binding. Measurements included pulmonary function, pressure-derived indices of respiratory mechanics, operating lung volumes, tidal flow-volume data, gas exchange, blood lactate, and symptoms. Residual volume and functional residual capacity were reduced with binding (77 ± 18 and 81 ± 11% of unbound, P < 0.05), vital capacity was increased (114 ± 9%, P < 0.05), whereas total lung capacity was relatively well preserved (99 ± 5%). During exercise, binding introduced a passive increase in transdiaphragmatic pressure, due primarily to an increase in gastric pressure. Active pressures during inspiration were similar across conditions. A sudden, sustained rise in operating lung volumes was evident in the unbound condition, and these volumes were shifted downward with binding. Expiratory flow limitation did not occur in any subject and there was substantial reserve to increase flow and volume in both conditions. V̇o2 was elevated with binding during the final stages of exercise (8-12%, P < 0.05), whereas blood lactate concentration was reduced (16-19%, P < 0.05). V̇o2/heart rate slopes were less steep with binding (62 ± 35 vs. 47 ± 24 ml/beat, P < 0.05). Ventilation, symptoms, and work rates were similar across conditions. The results suggest that abdominal binding shifts tidal breathing to lower lung volumes without influencing flow limitation, symptoms, or exercise tolerance. Changes in respiratory mechanics with binding may benefit O2 transport capacity by an improvement in central circulatory function., (Copyright © 2014 the American Physiological Society.)

Unlabelled: Abdominal binding has been shown to improve resting cardiorespiratory function in individuals with cervical SCI, but it is not yet clear whether this approach improves the exercise response., Objectives: To determine the effects of abdominal binding on parameters relating to wheelchair sports performance in highly-trained athletes with cervical SCI., Design: Repeated-measures field-based study., Methods: Ten Paralympic wheelchair rugby players with motor-complete SCI (C5-C7) completed a series of exercise tests in two conditions (bound and unbound). The following parameters were assessed: agility and acceleration/deceleration performance; cardiorespiratory function and gross efficiency during submaximal wheelchair propulsion; anaerobic performance and propulsion kinematics during a 30s Wingate test; repeated sprint performance during a 10×20m test; and aerobic performance during a repeated 4min push test., Results: Compared to unbound, 6 of 17 field-based performance measures changed significantly with binding. Time to complete the acceleration/deceleration test decreased (p=0.005), whereas distances covered during the repeated 4min push test increased (p<0.043). Binding elicited significant reductions in minute ventilation during submaximal wheelchair propulsion (p=0.040) as well as blood lactate accumulation and limb discomfort during the second set of the repeated 4min push test (p=0.012 and 0.022). There were no statistically significant effects of binding on any other variable., Conclusions: Abdominal binding improves some important measures of field-based performance in highly-trained athletes with cervical SCI. The changes may be attributable, at least in part, to improvements in trunk stability, ventilatory efficiency and/or haemodynamics., (Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

In this study, we assessed the influence that pre-exercise glucose ingestion of two concentrations has on the physiological responses of paraplegic athletes. Eight men with paraplegia ingested a drink containing 4% (low) or 11% (high) carbohydrate in a randomized double-blind crossover design, 20 min before exercise. The participants performed wheelchair exercise at 65% of peak oxygen uptake for 1 h followed by a 20 min performance test. During both trials, the physiological responses were similar and indicated steady-state exercise. At the onset of exercise, blood glucose concentrations in both trials increased after carbohydrate ingestion (P < 0.05) before returning to resting values after 20 min of exercise and there were no differences between trials. Free fatty acid concentrations increased from rest to 1 h of exercise in both trials, with a greater increase during the low carbohydrate trial that led to a difference in free fatty acids between trials at the end of the 1 h tests (P < 0.05). There was a tendency for the performance distances and power outputs achieved during the high carbohydrate trial to be greater than those achieved during the low carbohydrate trial (P= 0.08). In conclusion, when paraplegic athletes ingested low and high carbohydrate drinks before exercise, the decline in blood glucose concentrations was similar. The tendency for higher blood glucose concentrations, respiratory exchange ratios and power outputs and lower free fatty acid concentrations (P < 0.05) during the high carbohydrate trial suggests that a higher concentration of carbohydrate in a sports drink might be a better choice for paraplegic athletes.

Purpose: To study the effect of exercise volume on pre- and early-pubertal children's lipid-lipoprotein profile., Methods: Thirty-four children (15 girls) completed 12 wk of exercise training, preceded by a 12-wk control period. Sixteen (7 girls and 9 boys) expended an additional 422 +/- 5 kJ.kg BM (LOW, 100 kcal.kg), whereas 18 (8 girls and 10 boys) expended an additional 586 +/- 7 kJ.g (MOD, 140 kcal.kg) as a result of the training program. They all exercised on three nonconsecutive days per week at 80 +/- 1% HRpeak. Exercise duration was individualized to match energy expenditure targets. Plasma TG, TC, and HDL-C were measured precontrol, pretraining, and posttraining. LDL-C, TC/HDL-C, and LDL-C/HDL-C were also calculated., Results: Group mean lipid-lipoprotein concentrations did not change as a result of training energy expenditure in either of the groups (P > 0.05). Dietary composition, habitual physical activity, and body composition were also relatively stable over the intervention period (P > 0.05). In the LOW, but not the MOD group, peak VO2 (mL.kg.min) tended to increase over the intervention period (P = 0.07). Pearson's product moment correlation analyses indicated that pretraining concentrations of TG, TC, LDL-C, TC/HDL-C, and LDL-C/HDL-C were all related to the small changes seen in the lipid-lipoprotein profile (P < 0.01)., Conclusion: Additional energy expenditure of 422 or 586 kJ.kg, as a direct result of aerobic exercise training over a 12-wk period, did not cause significant alterations in the lipid-lipoprotein profile in pre- and early-pubertal children. This may indicate that the exercise volume was insufficient, the lipoprotein profiles of the majority of children in this study were classified as "desirable," or more likely a combination of these factors.

Purpose: This study examined the effects of the level of spinal cord injury upon the thermoregulatory responses of wheelchair athletes during prolonged wheelchair exercise in warm conditions., Methods: Eight tetraplegic (TP), 10 high-level paraplegic (HP), and 10 low-level paraplegic (LP) athletes exercised for 60 min at 60% [OV0312]O(2peak) in a warm environment (31.5 +/- 1.7 degrees C, 42.9 +/- 8.0% relative humidity). Skin temperature and aural temperature were monitored., Results: Aural temperature increased gradually during the exercise period by 1.1 +/- 0.3 and 1.4 +/- 0.5 degrees C for the HP and LP groups, with a more marked increase observed for the TP group (2.1 +/- 0.5 degrees C; P < 0.05). Upper-arm skin temperature was higher for the TP when compared with the HP and LP between 30 and 60 min (P < 0.05). Back skin temperature was higher for the TP when compared with the HP and LP between 45 and 60 min (P < 0.05). No differences were noted between groups for the thigh or calf skin temperatures. During recovery, skin temperature remained elevated for the TP group when compared with the HP and LP groups (P < 0.05). Heat storage was greatest for the TP athletes at the end of exercise and remained elevated throughout recovery (P < 0.05)., Conclusions: All athletes completed the exercise task even though the gradual increase in aural temperature observed for the HP and LP groups suggests a degree of thermal imbalance. However, this was much less than observed for TP athletes, who demonstrated a much greater imbalance in temperature regulation. Increasing the exercise or environmental strain may result in the thermoregulatory responses of athletes with a spinal cord injury being compromised.

Upper body exercise has many applications to the rehabilitation and maintenance of cardiovascular health of individuals who are unable to exercise their lower body. The hemodynamic loads of upper body aerobic exercise are characterized by relatively high blood pressure and relatively low venous return. It is not clear how the left ventricle adapts to the specific hemodynamic loads associated with this form of exercise training. The purpose of this study was to measure left ventricular structure and function in previously sedentary men by using echocardiography before and after 12 wk of aerobic arm-crank exercise training (n = 22) or a time control period (n = 22). Arm-crank peak oxygen consumption (in ml x kg(-1) x min(-1)) increased by 16% (P < 0.05) after training, and significant differences (P < 0.05) were found in wall thickness (from 0.86 to 0.99 cm) but not in left ventricular internal dimension in diastole or systole. This suggested a concentric pattern of left ventricular hypertrophy that persisted after scaling to changes in anthropometric characteristics. No differences (P < 0.05) were found for any measurements of resting left ventricular function. We conclude that upper body aerobic exercise training results in a specific left ventricular adaptation that is characterized by increased left ventricular wall thickness but no change in chamber dimension.

The thermoregulatory responses of upper-body trained athletes were examined at rest, during prolonged arm crank exercise and recovery in cool (21.5 +/- 0.9 degrees C, 43.9 +/- 10.1% relative humidity; mean +/- s) and warm (31.5 +/- 0.6 degrees C, 48.9 +/- 8.4% relative humidity) conditions. Aural temperature increased from rest by 0.7 +/- 0.7 degrees C (P< 0.05) during exercise in cool conditions and by 1.6 +/- 0.7 degrees C during exercise in warm conditions (P< 0.05). During exercise in cool conditions, calf skin temperature decreased (1.5 +/- 1.3 degrees C), whereas an increase was observed during exercise in warm conditions (3.0 +/- 1.7 degrees C). Lower-body skin temperatures tended to increase by greater amounts than upper-body skin temperatures during exercise in warm conditions. No differences were observed in blood lactate, heart rate or respiratory exchange ratio responses between conditions. Perceived exertion at 45 min of exercise was greater than that reported at 5 min of exercise during the cool trial (P< 0.05), whereas during exercise in the warm trial the rating of perceived exertion increased from initial values by 30 min (P < 0.05). Heat storage, body mass losses and fluid consumption were greater during exercise in warm conditions (7.06 +/- 2.25 J x g(-1) x degrees C(-1), 1.3 +/- 0.5 kg and 1,038 +/- 356 ml, respectively) than in cool conditions (1.35 +/- 0.23 J x g(-1) x degrees C(-1), 0.8 +/- 0.2 kg and 530 +/- 284 ml, respectively; P < 0.05). The results of this study indicate that the increasing thermal strain with constant thermal stress in warm conditions is due to heat storage within the lower body. These results may aid in understanding thermoregulatory control mechanisms of populations with a thermoregulatory dysfunction, such as those with spinal cord injuries.

Purpose: Postexercise hypotension may be the result of an impaired vasoconstrictor response. This hypothesis was investigated by examining the central and peripheral hemodynamic responses during supine and seated recovery after maximal upright exercise., Methods: After supine or seated baseline measurements, seven normotensive male volunteers completed a graded upright cycling protocol to volitional exhaustion. This was immediately followed by either supine or seated recovery. Measurements of pulsatile arterial blood pressure and central and peripheral hemodynamic variables recorded 30 min before exercise were compared with those taken throughout 60 min of recovery., Results: Compared with baseline, mean arterial pressure (MAP) was reduced after exercise (P < 0.05) although the degree of change was not different between the supine (-9 +/- 4 mm Hg) and seated positions (-6 +/- 2 mm Hg). This change in MAP was associated with a reduction in diastolic blood pressure (DBP) (P < 0.05) and arterial pulse pressure (APP) (P < 0.01) for the supine and seated positions, respectively. The reduction in APP during seated recovery was accompanied by a decline in stroke volume (SV) (P < 0.05), not seen in the supine position, that limited the contribution of cardiac output (CO) to the maintenance of MAP. This effect of seated recovery was compensated by greater systemic (SVR) and regional vascular resistances in the forearm (FVR) and the forearm skin (SkVRA). There was also evidence of an augmented return of FVR and SkVRA to resting levels in the seated position after exercise., Conclusion: The lower peripheral resistance in the supine compared with seated recovery position suggests there is potential for greater vasoconstriction, although this is not evoked to increase blood pressure. This further suggests that the arterial baroreceptor reflex is reset to a lower operating pressure after exercise.

Longitudinal paediatric population studies have provided evidence that the risk factor theory may be extended to children and adolescents. These studies could assist in identifying individuals at increased coronary risk. Numerous studies have focused on the effects of regular exercise on the paediatric lipoprotein profile, a recognised primary risk factor, with equivocal results. Cross-sectional comparisons of dichotomised groups provide the strongest evidence of an exercise effect. 'Trained' or 'active' children and adolescents demonstrate 'favourable' levels of high density lipoprotein-cholesterol (HDL-C), triacylglycerol, total cholesterol (TC)/HDL-C and low density lipoprotein-cholesterol (LDL-C)/HDL-C, whilst TC is generally unaffected. The evidence regarding LDL-C in these studies is equivocal. A possible self-selection bias means that a cause-effect relationship between exercise and the lipoprotein profile cannot be readily established from this design. Correlational studies are difficult to interpret because of differences in participant characteristics, methods employed to assess peak oxygen uptake and habitual physical activity (HPA), and the statistical techniques used to analyse multivariate data. Directly measured cardiorespiratory fitness does not appear to be related to lipoprotein profiles in the children and adolescents studied to date, although there are data to the contrary. The relationship with HPA is more difficult to decipher. The evidence suggests that a 'favourable' lipoprotein profile may be related to higher levels of HPA, although differences in assessment methods preclude a definitive answer. While few prospective studies exist, the majority of these longitudinal investigations suggest that imposed regular exercise has little, if any, influence on the lipoprotein levels of children and adolescents. However, most prospective studies have several serious methodological design weaknesses, including low sample size, inadequate exercise training volume and a lack of control individuals. Recent studies have suggested that increases in HDL-C and reductions in LDL-C may be possible with regular exercise. The identification of a dose-response relationship between exercise training and the lipoprotein profile during the paediatric years remains elusive.

Seven wheelchair athletes participated in this study. On separate occasions all athletes performed 60 min of arm crank ergometry and wheelchair ergometry at 60% of the ergometer specific VO2peak in cool conditions (21.5+/-1.3 degrees C; 54.2+/-6.3% relative humidity, 21.2+/-1.9 degrees C; 55.5+/-11.9% relative humidity, respectively). The order of testing was randomised. Aural and skin temperatures were continually measured throughout the 60 min test. Expired air was collected at 5, 15, 30, 45, and 60 min during the exercise period. Oxygen consumption was similar for both trials (1.09+/-0.21 and 1.16+/-0.331 x min-(-1), for the ACE and WCE trials, respectively). Heat storage was calculated at these time-points. Aural temperature was elevated from rest between 25 to 45 min of wheelchair ergometry (0.5+/-0.3 degrees C; P < 0.05) when compared to between 20 min of exercise and 5 min of recovery (0.6+/-0.3 degrees C; P<0.05) during the arm crank ergometry trial. On the cessation of arm crank ergometry, heat storage was elevated above values observed at 5 min of exercise (P < 0.05). On the cessation of wheelchair ergometry, heat storage was not elevated above values at 5 minutes of exercise. Upper arm skin temperature was cooler during wheelchair ergometry when compared to arm crank ergometry (P<0.05). All other skin temperature responses were similar during both exercise modes. The efficiency of arm crank ergometry was greater than wheelchair ergometry throughout the exercise period (18.5+/-3.5 % and 8.9+/-3.7% at 60 minutes of exercise, respectively; P < 0.05). The results of this study suggest that although ACE demonstrates greater efficiency than WCE prolonged arm crank ergometry elicited greater thermal and physiological strain when compared with prolonged wheelchair ergometry. The lower thermal strain during WCE was suggested to be related to the propulsion biomechanics which may result in some degree of local cooling, and consequently heat dissipation, when compared to ACE. Due to the greater thermal strain during arm crank ergometry, it is recommended that for studies examining the exercise responses of wheelchair users wheel-chair ergometry should be employed.

The purpose of this study was to determine (1) the repeatability of a currently recommended protocol for determination of VO2 peak during upper body exercise involving a crank rate of 60 rev min-1 (Hale et al. 1988), (2) whether employing a higher crank rate (70 rev min-1) elicits higher VO2 peak values; (3) whether including an additional exercise stage 5 min after volitional exhaustion would elicit higher VO2 peak values. Twenty subjects (mean +/- SD) age, height and body mass were 22.8 +/- 1.8 years, 176 +/- 5.0 cm and 77.5 +/- 4.0 kg, respectively) visited the laboratory on three separate occasions. Subjects performed a different test to determine upper body VO2 peak on each visit. The tests were continuous and incremental in nature and were performed on a Monark cycle ergometer (Model 814E) adapted for arm exercise. Test 1 required subjects to exercise at a crank rate of 60 rev min-1 (60RPM-1). Test 2 was identical to test 1 (60RPM-2) but after 5 min recovery from the test subjects performed a further exercise stage (60RPM-F). Test 3 employed a crank rate of 70 rev min-1 (70RPM). Five minutes after volitional exhaustion a further exercise stage was performed (70RPM-F). The levels of agreement for the 60 rev min-1 protocol were +/-0.50 1 min-1. All VO2 peak values achieved were within these limits. However, a higher VO2 peak was achieved by employing a crank rate of 70 rev min-1 (p < 0.05). The VO2 peak achieved for 60RPM-F was similar to 60RPM whereas the VO2 peak for 70RPM-F tended to be less than that for 70RPM (p = 0.064). The results of this study suggest that the 60 rev min-1 protocol can reliably determine VO2 peak, however it would appear to be more appropriate to employ a 70 rev min-1 protocol as higher values were attained.

The thermoregulatory responses of ten paraplegic (PA; T3/4-L4) and nine able-bodied (AB) upper body trained athletes were examined at rest and during prolonged arm-cranking exercise and passive recovery. Exercise was performed for 90 min at 80% peak heart rate, and at 21.5 (1.7) degrees C and 47.0 (7.8)% relative humidity on a Monark cycle ergometer (Ergomedic 814E) adapted for arm exercise. Mean peak oxygen uptake values for the PA and AB athlete groups were 2.12 (0.41) min(-1) and 3.19 (0.38) l x min(-1), respectively (P<0.05). At rest, there was no difference in aural temperature between groups [36.2 (0.4) degrees C for both groups]. However, upper body skin temperatures for the PA athletes were approximately 1.0 degrees C warmer than for the AB athletes, whereas lower body skin temperatures were cooler than those for the AB athletes (1.3 degrees C and 2.7 degrees C for the thigh and calf, respectively). Upper and lower body skin temperatures for the AB athletes were similar. During exercise, blood lactate peaked after 15 min of exercise for both groups [3.33 (1.26) mmol x l(-1) and 4.30 (1.03) mmol x l(-1) for the PA and AB athletes, respectively, P<0.05] and decreased throughout the remainder of the exercise period. Aural temperature increased by 0.7 (0.5) degrees C and 0.6 (0.4) degrees C for the AB and PA athletes, respectively. Calf skin temperature for the PA athletes increased during exercise by 1.4 (2.8) degrees C (P<0.05), whereas a decrease of 0.8 (2.0) degrees C (P<0.05) was observed for the AB athletes. During the first 20 min of recovery from exercise, the calf skin temperature of the AB athletes decreased further [-2.6 (1.3) degrees C; P<0.05]. Weight losses and changes in plasma volume were similar for both groups [0.7 (0.5) kg and 0.7 (0.4) kg; 5.4 (4.9)% and 9.7 (6.2)% for the PA and AB athletes, respectively]. In conclusion, the results of this study suggest that the PA athletes exhibit different thermoregulatory responses at rest and during exercise and passive recovery to those of upper body trained AB athletes. Despite this, during 90 min of arm-crank exercise in a cool environment, the PA athletes appeared to be at no greater thermal risk than the AB athletes.