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Hill, MW, Roberts, M, Price, MJ, and Kay, AD. Effects of flywheel training with eccentric overload on standing balance, mobility, physical function, muscle thickness, and muscle quality in older adults. J Strength Cond Res 36(11): 3190-3199, 2022-This study investigated the effects of a 6-week eccentric overload flywheel training program on vastus lateralis (VL) and gastrocnemius medialis (GM) muscle thickness and muscle quality (echo intensity), mobility (Timed Up and Go [TUG]), physical function (sit-to-stand), and balance (postural sway) performance. Nineteen subjects were assigned to either a flywheel training group ( n = 11, age = 66.4 ± 5.2 years) or a control group ( n = 8, age = 65.9 ± 3.8 years). The flywheel group underwent twice weekly squat and calf raise exercises for 6 weeks with outcome measures assessed before and after training or a time-matched control period. Throughout the training, subjects were instructed to contract as fast as possible with maximal effort during the concentric phase and to maximally resist the pull during the eccentric phase. The alpha value was a priori set at p0.05. Statistically significant ( p0.05) mean ( SD ) increases in right and left VL (7.6-9.6 ± 7.7-9.8%) and GM (8.6-8.7 ± 6.4-11.5%) muscle thickness and a reduction in VL (10.2-11.3 ± 5.9-7.9%) and GM (11.7-11.9 ± 5.6-9.6%) echo intensity were accompanied by faster TUG time (13.7 ± 7.0%) improved sit-to-stand performance (17.8-23.5 ± 7.6 - 13.4%) and reduced postural sway (29.7-42.3 ± 13.2-24.2%) after 6 weeks of flywheel training. There were no differences in any outcome measures between the treatment and control group at baseline ( p0.05). Overall, we observed substantial gains in muscle thickness and muscle quality, in addition to enhanced physical function, balance, and mobility performance among older adults after flywheel training, which may have important implications for preserving the functional capacity of older adults.

Objectives Provide normative values for cervical range of motion and describe trends in school age rugby union players. Design Cross-sectional study. Setting National 3 level club. Participants 59 school age rugby union players across under 8 (n = 8), under 9 (n = 9), under 10 (n = 15), under 13 (n = 13) and under 15 (n = 15) categories. Main outcome measures Cervical range of motion using a cervical range of motion device (CROM) to determine values for active range of motion. Results This study established mean ranges of motion for each age group. Pooled mean ranges with standard deviations for each direction were, flexion 66° (±11), extension 73° (±17), left rotation 69° (±9), right rotation 74° (±10), left lateral flexion 53° (±10) and right lateral flexion 49° (±12). No statistically significant differences were observed between the age groups, however, downward trends in lateral flexion were observed as age increased. School age rugby players had greater range of motion than senior playing counterparts. Conclusions No statistically significant differences in ranges of motion were observed between the age groups of under 8 through to under 15. However, downward trends in some ranges of motion highlight the need for age specific monitoring for potential adaptations to continued playing and comparison to age matched non-rugby players. Inclusion of other risk factors such as head re-positioning sense should also be evaluated to help guide injury risk reduction strategies.

The aim of this study was to determine the physiological demands of epee fencing performance. Eight elite male epee fencers competed in a competition consisting of 7 Poule and 7 Direct Elimination ...

Objectives: Athletes with high level spinal cord injuries (tetraplegia) are under greater thermal strain during exercise than the able-bodied. The purpose of this study was to investigate the effectiveness of pre-cooling using an ice vest and the combination of pre-cooling and cooling during play using water sprays in athletes with tetraplegia.\ud \ud Design: Counter-balanced, cross-over design.\ud \ud Methods: Eight wheelchair rugby players with tetraplegia completed a 60 min intermittent sprint protocol (ISP) on a wheelchair ergometer in 20.2 °C ± 0.2 °C and 33.0% ± 3.1% relative humidity. The ISP was conducted on three occasions; no cooling (NC), pre-cooling with an ice vest (P) and pre-cooling with an ice vest and water sprays between quarters (PW). Gastrointestinal (Tgi) temperature, mean skin temperature (Tsk) and perceptual responses were measured throughout.\ud \ud Results: At the end of pre-cooling, the change in Tgi was not significantly different between conditions (P > 0.05) but the change in Tsk was significantly greater in P and PW compared to NC (P < 0.001). The change in Tgi over the ISP was significantly lower in PW and P compared to NC (P < 0.05), whilst the change in Tsk was lower in PW compared to P and NC (P < 0.05). Cooling had no effect on performance or perceptual responses (P > 0.05).\ud \ud Conclusions: Water spraying between quarters combined with pre-cooling using an ice vest lowers thermal strain to a greater degree than pre-cooling only in athletes with tetraplegia, but has no effect on simulated wheelchair rugby performance or perceptual responses.

Presented in this infographic is a summary of studies investigating the thermoregulatory impairment of athletes with a spinal cord injury during real-world sporting scenarios. The infographic depicts the heightened thermal strain experienced by athletes with tetraplegia (high level lesions), both compared to athletes with paraplegia (low level lesions) and within the sport of wheelchair rugby. In addition to the cooling interventions presented, the infographic highlights the significant need for appropriate interventions to reduce the risk of overheating and potential performance decrements. This infographic was field tested with those who work within a wheelchair sports environment, ranging from practitioners, researchers, athletes with an SCI and sports clinicians. The experimental studies were also designed in consultation with the wheelchair rugby coaches and players.

Objective To investigate manual therapist's knowledge and beliefs of working with Transplantee Athletes (TxA) at Transplant Games. Design On-line questionnaire. Participants Thirty present and previous members of Transplant Sport ‘therapy team’ (age; 35 ± 14 years, 24 female). Main outcome measures Questions concerned demographics and general information on the background of the therapists. Closed questions with rating statements concerning beliefs when treating TxA and open questions asking for advice the participants would give to colleagues and further information they would like to have available to them. Results TxA were thought to be a vulnerable group of athletes requiring special precautions and considerations. Two areas of information evolved: “general advice for TxA management” and “specific advice for therapists”. General advice was to understand TxAs and be vigilant with hygiene. Specific therapy advice was to avoid grade V manipulations and care with taping and massage, because of complications resulting from side effects of long-term medication. Conclusion There appears to be a lack of research-based evidence to guide practitioners in their management of TxAs. Generic, good advice is now available from experienced practitioners however there is a paucity of research evidence to support this. Thus, there is a potential danger of being overcautious in approaches to treatment which ultimately may impact on athletic performance.

© 2016 Informa UK Limited, trading as Taylor & Francis Group The purpose of this study was to compare arm–leg coordination and kinematics during 100 m breaststroke in 26 (8 female; 18 male) specialist breaststroke swimmers. Laps were recorded using three 50-Hz underwater cameras. Heart rate and blood lactate were measured pre- and post-swim. Arm–leg coordination was defined using coordination phases describing continuity between recovery and propulsive phases of upper and lower limbs: coordination phase 1 (time between end of leg kick and start of the arm pull phases); and coordination phase 2 (time between end of arm pull and start of leg kick phases). Duration of stroke phases, coordination phases, swim velocity, stroke length (SL), stroke rate (SR) and stroke index (SI) were analysed during the last three strokes of each lap that were unaffected by turning or finishing. Significant changes in velocity, SI and SL (P

BACKGROUND The purpose of this study was to determine the cardiorespiratory demands of standing and wheelchair (seated) fencing in a group of able-bodied fencers during simulated competitive bouts. METHODS Participants were ten male able-bodied fencers of regional level with previous training experience in wheelchair fencing. After a standardized warm-up, participants performed two series of simulated competitive epee bouts (5 and 15 touches) in a random order, either while standing or while sitting in a wheelchair. Expired gas was analyzed for oxygen consumption (VO2) and respiratory exchange ratio (RER) and heart rate were continually monitored. Energy expenditure (EE) was subsequently calculated. RESULTS VO2, HR and EE peak responses were greater during standing than seated fencing (P

Nevin, JP, Smith, P, Waldron, M, Patterson, S, Price, M, Hunt, A, and Blagrove, R. Efficacy of an 8-week concurrent strength and endurance training program on hand cycling performance. J Strength Cond Res 32(7): 1861-1868, 2018-The aim of this study was to investigate the effects of an 8-week concurrent strength and endurance training program in comparison with endurance training only on several key determinants of hand cycling performance. Five H4 and 5 H3 classified hand cyclists with at least 1 year's hand cycling training history consented to participate in the study. Subjects underwent a battery of tests to establish body mass, body composition, V[Combining Dot Above]O2peak, maximum aerobic power, gross mechanical efficiency (GME), maximal upper-body strength, and 30-km time-trial performance. Subjects were matched into pairs based on 30-km time-trial performance and randomly allocated to either a concurrent strength and endurance or endurance training only, intervention group. After an 8-week training program based on a conjugated block periodization model, subjects completed a second battery of tests. A mixed model, 2-way analysis of variance revealed no significant changes between groups. However, the calculation of effect sizes (ESs) revealed that both groups demonstrated a positive improvement in most physiological and performance measures with subjects in the concurrent group demonstrating a greater magnitude of improvement in body composition (ES -0.80 vs. -0.22), maximal aerobic power (ES 0.97 vs. 0.28), GME (ES 0.87 vs. 0.63), bench press 1 repetition maximum (1RM) (ES 0.53 vs. 0.33), seated row 1RM (ES 1.42 vs. 0.43), and 30-km time-trial performance (ES -0.66 vs. -0.30). In comparison with endurance training only, an 8-week concurrent training intervention based on a conjugated block periodization model seems to be a more effective training regime for improving the performance capabilities of hand cyclists.

The purpose of this study was to investigate the effects of holding external loads on postural sway during upright stance across age decades. Sixty-five healthy adults (females, n = 35), aged 18-80 years were assessed in four conditions; (1) standing without holding a load, holding a load corresponding to 5% body mass in the (2) left hand, (3) right hand and (4) both hands. The centre of pressure (COP) path length and anteroposterior and mediolateral COP displacement were used to indirectly assess postural sway. External loading elicited reductions in COP measures of postural sway in older age groups only (P 0.05). No changes were observed in younger or intermediate aged adults (P 0.05). Holding external loads during standing is relevant to many activities of daily living (i.e. holding groceries). The reduction in postural sway may suggest this type of loading has a stabilising effect during quiet standing among older adults.

The purpose of this study was to determine whether a player’s physical impairment or activity profile was related to the amount of thermal strain experienced during wheelchair rugby match play. 17 elite wheelchair rugby players played a competitive match, whilst activity profiles, measures of core and skin temperature, heart rate and perceptual responses were taken. Players were divided into 2 groups depending on their physical impairment: players with a cervical spinal cord injury, (n=10) or non-spinal related physical impairment (n=7). Total distance was lower (4 842±324 vs. 5 541±316 m, p

This study examined the acute effects of NaHCO3 ingestion on repetitions to failure and rating of perceived exertion in the back squat and bench press in trained men. Eight resistance-trained men took part in this double-blind, randomized crossover experimental study whereby they ingested NaHCO3 (0.3 g·kg(-1) body mass) or placebo (sodium chloride NaCl: 0.045 g·kg(-1) body mass) solution 60 minutes before completing a bout of resistance exercise (3 sets of bench press and back squat exercise to failure at an intensity of 80% 1 repetition maximum). Experimental conditions were separated by at least 48 hours. Participants completed more repetitions to failure in the back squat after NaHCO3 ingestion (p = 0.04) but not for bench press (p = 0.679). Mean ± SD of total repetitions was 31.3 ± 15.3 and 24.6 ± 16.2 for back squat and 28.7 ± 12.2 and 26.7 ± 10.2 for bench press in NaHCO3 and placebo conditions, respectively. Repetitions to failure decreased as set increased for the back squat and bench press (p = 0.001, both). Rating of perceived exertion significantly increased with set for the back squat and bench press (p = 0.002, both). There was no significant change in blood lactate across time or between conditions. There were however treatment × time interactions for blood pH (p = 0.014) and blood HCO3 concentration (p = 0.001). After ingestion, blood pH and HCO3 (p = 0.008) concentrations were greater for the NaHCO3 condition compared with the placebo condition (p < 0.001). The results of this study suggest that sodium bicarbonate ingestion can enhance resistance exercise performance using a repetition to failure protocol in the first exercise in a resistance exercise session.

Ten healthy, non-cycling trained males (age: 21.2 ± 2.2 years, body mass: 75.9 ± 13.4 kg, height: 178 ± 6 cm, [Vdot]O2PEAK: 46 ± 10 ml · kg(-1) · min(-1)) performed a graded incremental exercise test, two familiarisation trials and six experimental trials. Experimental trials consisted of cycling to volitional exhaustion at 100%, 110% and 120% WPEAK, 60 min after ingesting either 0.3 g · kg(-1) body mass sodium bicarbonate (NaHCO3) or 0.1 g · kg(-1) body mass sodium chloride (placebo). NaHCO3 ingestion increased cycling capacity by 17% at 100% WPEAK (327 vs. 383 s; P = 0.02) although not at 110% WPEAK (249 vs. 254 s; P = 0.66) or 120% WPEAK (170 vs. 175 s; P = 0.60; placebo and NaHCO3 respectively). Heart rate (P = 0.02), blood lactate (P = 0.001), pH (P0.001), [HCO3 (-)], (P0.001), and base excess (P0.001) were greater in all NaHCO3 trials. NaHCO3 attenuated localised ratings of perceived exertion (RPEL) to a greater extent than placebo only at 100% WPEAK (P0.02). Ratings of abdominal discomfort and gut fullness were mild but higher for NaHCO3. NaHCO3 ingestion significantly improves continuous constant load cycling at 100% WPEAK due to, in part, attenuation of RPEL.

The aims were to undertake a movement analysis of a simulated epee fencing competition and to develop and validate a laboratory based protocol (LAB). Seven male club epee fencers undertook a simula...

We examined the effects of concomitant increases in crank rate and power output on incremental arm crank ergometry. Ten healthy males undertook three incremental upper body exercise tests to volitional exhaustion. The first test determined peak minute power. The subsequent tests involved arm cranking at an initial workload of 40% peak minute power with further increases of 10% peak minute power every 2 min. One involved a constant crank rate of 70 rev · min(-1), the other an initial crank rate of 50 rev · min(-1) increasing by 10 rev · min(-1) every 2 min. Fingertip capillary blood samples were analysed for blood lactate at rest and exhaustion. Local (working muscles) and cardiorespiratory ratings of perceived exertion (RPE) were recorded at the end of each exercise stage. Heart rate and expired gas were monitored continuously. No differences were observed in peak physiological responses or peak minute power achieved during either protocol. Blood lactate concentration tended to be greater for the constant crank rate protocol (P = 0.06). Test duration was shorter for the increasing than for the constant crank rate protocol. The relationship between local RPE and heart rate differed between tests. The results of this study show that increasing cadence during incremental arm crank ergometry provides a valid assessment of peak responses over a shorter duration but alters the heart rate-local RPE relationship.

Resting energy expenditure of persons with a spinal cord injury (SCI) is generally lower than that seen in able-bodied (AB) individuals due to the reduced amounts of muscle mass and sympathetic nervous system available. However, outside of clinical studies, much less data is available regarding athletes with an SCI. In order to predict the energy expenditure of persons with SCI, the generation and validation of prediction equations in relation to specific levels of SCI and training status are required. Specific prediction equations for the SCI would enable a quick and accurate estimate of energy requirements. When compared with the equivalent AB individuals, sports energy expenditure is generally reduced in SCI with values representing 30-75% of AB values. The lowest energy expenditure values are observed for sports involving athletes with tetraplegia and where the sport is a static version of that undertaken by the AB, such as fencing. As with AB sports there is a lack of SCI data for true competition situations due to methodological constraints. However, where energy expenditure during field tests are predicted from laboratory-based protocols, wheelchair ergometry is likely to be the most appropriate exercise mode. The physiological and metabolic responses of persons with SCI are similar to those for AB athletes, but at lower absolute levels. However, the underlying mechanisms pertaining to substrate utilization appear to differ between the AB and SCI. Carbohydrate feeding has been shown to improve endurance performance in athletes with generally low levels of SCI, but no data have been reported for mid to high levels of SCI or for sport-specific tests of an intermittent nature. Further research within the areas reviewed may help to bridge the gap between what is known regarding AB athletes and athletes with SCI (and other disabilities) during exercise and also the gap between clinical practice and performance.

Purpose:Individuals with a spinal-cord injury have impaired thermoregulatory control due to a loss of sudomotor and vasomotor effectors below the lesion level. Thus, individuals with high-level lesions (tetraplegia) possess greater thermoregulatory impairment than individuals with lower-level lesions (paraplegia). Previous research has not reflected the intermittent nature and modality of wheelchair court sports or replicated typical environmental temperatures. Hence, the purpose of this study was to investigate the thermoregulatory responses of athletes with tetraplegia and paraplegia during an intermittent-sprint protocol (ISP) and recovery in cool conditions.Methods:Sixteen wheelchair athletes, 8 with tetraplegia (TP, body mass 65.2 ± 4.4 kg) and 8 with paraplegia (body mass 68.1 ± 12.3 kg), completed a 60-min ISP in 20.6°C ± 0.1°C, 39.6% ± 0.8% relative humidity on a wheelchair ergometer, followed by 15 min of passive recovery. Core temperature (Tcore) and mean (Tsk) and individual skin temperatures were measured throughout.Results:Similar external work (P = .70, ES = 0.20) yet a greater Tcore (P < .05, ES = 2.27) and Tsk (P < .05, ES = 1.50) response was demonstrated by TP during the ISP.Conclusions:Despite similar external work, a marked increase in Tcore in TP during exercise and recovery signifies that thermoregulatory differences between the groups were predominantly due to differences in heat loss. Further increases in thermal strain were not prevented by the active and passive recovery between maximal-effort bouts of the ISP, as Tcore continually increased throughout the protocol in TP.

The principal aim of this study was to examine how different ramp rates influenced the attainment of peak physiological responses during incremental arm crank ergometry (ACE). Additionally, the study examined whether there was any evidence for the development of an "excess" VO (2) during ACE due to upward curvi-linearity in the VO (2)-work rate relationship, and whether this was influenced by the ramp rate. Sixteen physically active, though non-specifically trained, men (mean +/- S age 30 +/- 8 years; height 1.79 +/- 0.07 m; body mass 84.7 +/- 13.2 kg) volunteered to participate. Having completed a familiarisation test, all subjects returned to the laboratory to complete two ramp tests on an electrically-braked ergometer in a counter-balanced order. Both ramp tests started at 60 W with work rate subsequently incremented by either 6 or 12 W . min (-1). Pulmonary gas exchange was measured breath-by-breath throughout the tests. Subjects achieved a greater final work rate during the 12 W . min (-1) test compared to the 6 W . min (-1) test (168 +/- 28 vs. 149 +/- 26 W; p < 0.001). The VO (2peak) (3.06 +/- 0.65 vs. 2.96 +/- 0.48 L . min (-1); p = 0.27), HR (peak) (179 +/- 15 vs. 177 +/- 16 b . min (-1); p = 0.17) and V.E (peak) (112 +/- 22 vs. 105 +/- 16 L . min (-1); p = 0.09) were not different between the tests, but VCO (2peak) (3.54 +/- 0.64 vs. 3.27 +/- 0.46 L . min (-1); p = 0.01) RER (peak) (1.17 +/- 0.07 vs. 1.11 +/- 0.06; p < 0.001), and end-exercise blood (lactate) (11.9 +/- 2.1 vs. 10.8 +/- 2.6 mmol . L (-1); p = 0.005) were all higher in the 12 W . min (-1) test. An "excess" VO (2) was observed in 13 out of 16 tests at 12 W . min (-1) and in 15 out of 16 tests at 6 W . min (-1). Neither the magnitude of the "excess" VO (2) (0.42 +/- 0.41 vs. 0.37 +/- 0.18 L . min (-1); p = 0.66) nor the VO (2) at which the V.O (2)-work rate relationship departed from linearity (2.17 +/- 0.34 vs. 2.18 +/- 0.32 L . min (-1); p = 0.94) were significantly different between the two ramp tests. These data indicate that differences in ramp rate within the range of 6 - 12 W . min (-1) influence the peak values of work rate, VCO (2) and RER, but do not influence peak values of VO (2) or HR during ACE. The development of an "excess" VO (2) appears to be a common feature of ramp exercise in ACE, although the mechanistic basis for this effect is presently unclear.

The increased participation in wheelchair sports in conjunction with environmental challenges posed by the most recent Paralympic venues has stimulated interest into the study of thermoregulation of wheelchair users. This area is particularly pertinent for the spinal cord injured as there is a loss of vasomotor and sudomotor effectors below the level of spinal lesion. Studies within this area have examined a range of environmental conditions, exercise modes and subject populations. During exercise in cool conditions (15-25 degrees C), trained paraplegic individuals (thoracic or lumbar spinal lesions) appear to be at no greater risk of thermal injury than trained able-bodied individuals, although greater heat storage for a given metabolic rate is evident. In warm conditions (25-40 degrees C), trained subjects again demonstrate similar core temperature responses to the able-bodied for a given relative exercise load but elicit increased heat storage within the lower body and reduced whole-body sweat rates, increasing the risk of heat injury. The few studies examining a wide range of lesion levels have noted that, for paraplegic individuals where heat production is matched by available sweating capacity, excessive heat strain may be offset. Studies relating to tetraplegic subjects (cervical spinal lesions) are fewer in number but have consistently shown this population to elicit much faster rates of core and skin temperature increase and thermal imbalance in both cool and warm conditions than paraplegic individuals. These responses are due to the complete absence or severely reduced sweating capacity in tetraplegic subjects. During continuous exercise protocols, the main thermal stressor for tetraplegic subjects appears to be environmental heat gain, whereas during an intermittent-type exercise protocol it appears to be metabolic heat production. Fluid losses during exercise and heat retention during passive recovery from exercise are related to lesion level. Future research is recommended to focus on the specific role of absolute and relative metabolic rates, sweating responses, training status and more sport- and vocation-specific exercise protocols.

This study examined the effects of variations in crank rate on physiological responses during submaximal arm ergometry. Fifteen non-specifically trained male subjects volunteered to participate in this study. Each subject undertook a discontinuous arm crank ergometry test (30, 50, 70, 90 W) on three separate occasions using crank rates of 50, 70, and 90 rev.min(-1). Respiratory parameters and heart rate were continuously monitored. An 80-microL capillary blood sample was obtained immediately following each exercise bout for the determination of whole blood lactate. Measures of efficiency were calculated using specific caloric equivalents of oxygen consumption (V(O2)). Heart rate was lowest (p0.05) at 30, 50, and 70 W using 50 rev.min(-1). Values of gross and net efficiency tended to be higher (p0.05) using 50 rev.min (-1) at the lower absolute workloads, but no differences (p0.05) were observed between the three crank rates at 90 W. No differences (p0.05) were observed between crank rates for delta efficiency. This study confirms that variations in crank rate can influence gross and net values of V(O2) and exercise efficiency at low absolute workloads, but crank rate ceases to be an influential factor at moderate workloads. Further research is required to identify the specific mechanisms underpinning the observations reported in the present study relating to the interaction between crank rate, workload, and exercise efficiency during arm crank ergometry.

The present study examined the impact of two exercise protocols on the attainment of peak physiological responses during arm crank ergometry (ACE). Fourteen physically active, although non-specifically trained male subjects completed two V.O (2) peak tests using an electrically braked arm ergometer (Lode Angio, Groningen, Netherlands). The tests consisted of a stepwise or rampwise increase in external workload. The order of tests was randomised and each test was separated by at least two days. Respiratory data were collected continuously using an on-line gas analysis system with sample time set at 30 s. Fingertip capillary blood samples ( approximately 20 microL) were collected at volitional exhaustion and at minute intervals for 7 min of passive recovery for the determination of peak whole blood lactate concentration. Time on the test (T (lim); s), peak minute power (PMP; W), and total work done (TWD; kJ) were also recorded. In addition to determining systematic bias using separate independent t-tests, the level of agreement was also examined by way of calculating the 95 % limits of agreement. Sub-maximal values of V.O (2), V.E, and HR were similar (p > 0.05) between test when the amount of external work completed was taken into consideration. There was no systematic bias (p > 0.05) for mean (+/- s) peak values of V.O (2) (3.12 [0.37] vs. 3.04 [0.38] L . min (-1)) or any other parameter between the step and ramp tests, respectively. Mean values of T (lim), PMP, and TWD were also similar (p > 0.05) between tests. However, the level of agreement for peak values of all test parameters was low. It is therefore concluded that while either test can be considered as being suitable for the purpose of eliciting V.O (2) peak and other physiological responses using ACE, they should not be used interchangeably for the purpose of assessing parameters linked to the aerobic capacity of the upper-body.

The Raman spectra of the ammonia-borane complex, NH3BH3, have been investigated as a function of pressure up to 40 kbar. Vibrational modes involving the NH3 group show negative pressure dependences, supporting the existence of the dihydrogen bond, but the vibrations of the BH3 group have a positive dependence. Two transitions were observed in the solid phase under pressure, in contrast to the temperature behavior, where a single transition occurs. Factor group splitting occurs for the degenerate vibrations, and this allows the correct assignment of the observed vibrations.

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 (P0.05) during exercise in cool conditions and by 1.6 +/- 0.7 degrees C during exercise in warm conditions (P0.05). 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 (P0.05), whereas during exercise in the warm trial the rating of perceived exertion increased from initial values by 30 min (P0.05). 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; P0.05). 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.

Cooling strategies that help prevent a reduction in exercise capacity whilst exercising in the heat have received considerable research interest over the past 3 decades, especially in the lead up to a relatively hot Olympic and Paralympic Games. Progressing into the next Olympic/Paralympic cycle, the host, Rio de Janeiro, could again present an environmental challenge for competing athletes. Despite the interest and vast array of research into cooling strategies for the able-bodied athlete, less is known regarding the application of these cooling strategies in the thermoregulatory impaired spinal cord injured (SCI) athletic population. Individuals with a spinal cord injury (SCI) have a reduced afferent input to the thermoregulatory centre and a loss of both sweating capacity and vasomotor control below the level of the spinal cord lesion. The magnitude of this thermoregulatory impairment is proportional to the level of the lesion. For instance, individuals with high-level lesions (tetraplegia) are at a greater risk of heat illness than individuals with lower-level lesions (paraplegia) at a given exercise intensity. Therefore, cooling strategies may be highly beneficial in this population group, even in moderate ambient conditions (~21 °C). This review was undertaken to examine the scientific literature that addresses the application of cooling strategies in individuals with an SCI. Each method is discussed in regards to the practical issues associated with the method and the potential underlying mechanism. For instance, site-specific cooling would be more suitable for an athlete with an SCI than whole body water immersion, due to the practical difficulties of administering this method in this population group. From the studies reviewed, wearing an ice vest during intermittent sprint exercise has been shown to decrease thermal strain and improve performance. These garments have also been shown to be effective during exercise in the able-bodied. Drawing on additional findings from the able-bodied literature, the combination of methods used prior to and during exercise and/or during rest periods/half-time may increase the effectiveness of a strategy. However, due to the paucity of research involving athletes with an SCI, it is difficult to establish an optimal cooling strategy. Future studies are needed to ensure that research outcomes can be translated into meaningful performance enhancements by investigating cooling strategies under the constraints of actual competition. Cooling strategies that meet the demands of intermittent wheelchair sports need to be identified, with particular attention to the logistics of the sport.

This study examined the effects of combined glucose and sodium bicarbonate ingestion prior to intermittent exercise. Ninemales (mean ± s age 25.4 ± 6.6 years, body mass 78.8 ± 12.0 kg, maximal oxygen uptake (VO2 max)) 47.0 ± 7 ml · kg · min(-1)) undertook 4 × 45 min intermittent cycling trials including 15 × 10 s sprints one hour after ingesting placebo (PLA), glucose (CHO), sodium bicarbonate (NaHCO3) or a combined CHO and NaHCO3 solution (COMB). Post ingestion blood pH (7.45 ± 0.03, 7.46 ± 0.03, 7.32 ± 0.05, 7.32 ± 0.01) and bicarbonate (30.3 ± 2.1, 30.7 ± 1.8, 24.2 ± 1.2, 24.0 ± 1.8 mmol · l(-1)) were greater for NaHCO3 and COMB when compared to PLA and CHO, remaining elevated throughout exercise (main effect for trial; P0.05). Blood lactate concentration was greatest throughout exercise for NaHCO3 and COMB (main effect for trial; P0.05). Blood glucose concentration was greatest 15 min post-ingestion for CHO followed by COMB, NaHCO3 and PLA (7.13 ± 0.60, 5.58 ± 0.75, 4.51 ± 0.56, 4.46 ± 0.59 mmol · l(-1), respectively; P0.05). Gastrointestinal distress was lower during COMB compared to NaHCO3 at 15 min post-ingestion (P0.05). No differences were observed for sprint performance between trials (P = 1.00). The results of this study suggest that a combined CHO and NaHCO3 beverage reduced gastrointestinal distress and CHO availability but did not improve performance. Although there was no effect on performance an investigation of the effects in more highly trained individuals may be warranted.

The purpose of this study was to determine the effects of sodium bicarbonate (NaHCO3) ingestion on intermittent running and subsequent performance. Eight healthy men volunteered to take part in the study. One hour after the ingestion of either NaHCO(3) or placebo (sodium chloride; NaCl) participants undertook 20 x 24-second runs on a motorized treadmill at the velocity eliciting maximal oxygen uptake (100% v-VO(2)max). After sprint 20 participants performed a run to volitional exhaustion at 120% v-VO(2)max. Capillary blood samples for blood pH, bicarbonate ([HCO(3)]), and lactate ([Bla]) concentration were taken pre and postingestion, every fifth sprint and after the performance run. After ingestion of NaHCO(3), blood [HCO(3)] increased from resting values (p0.05), and the increase in pH approached significance. Blood [HCO(3)(-)] continually decreased throughout intermittent exercise (p0.05) and decreased further after performance in both trials (p0.05). [Bla] was similar in both trials throughout intermittent exercise but was greater at exhaustion for NaHCO(3) (main effect for trial; p0.05). There was no significant difference in performance of the group between trials (78 +/- 22 and 75 +/- 22 seconds for NaHCO(3) and NaCl, respectively). The intercept of the relationships between [Bla] and [HCO(3)(-)] and between [Bla] and pH was greater during NaHCO(3) (p0.05), whereas the relationship between pH and [HCO(3)(-)] was unchanged (p0.05). The results of this study suggest that the ingestion of NaHCO(3) before intermittent type exercise was sufficient to induce metabolic alkalosis but did not significantly affect performance. However, because significant individual variations in performance were observed, an individual approach to bicarbonate ingestion is recommended based on the intensity and duration of the required performance.

This study examined the increase in blood pH and bicarbonate concentration after ingestion of a standard sodium bicarbonate solution. Peak blood pH and bicarbonate concentration occurred between 60 and 90 minutes. Values decreased over the remainder of the ingestion period although still elevated above preingestion levels.

Precooling has been shown to enhance performance in repeated sprint exercise in able-bodied subjects in a hot environment. Spinal cord injury causes thermoregulatory impairment with a detrimental effect on performance. This study assessed whether cooling strategies before and during exercise in the heat enhances sprint performance in athletes with tetraplegia.Eight male athletes with tetraplegia performed intermittent arm crank exercise in the heat (32.0 degrees C (0.1 degrees C); humidity, 50% (0.1%)) for a maximum of 60 min or until exhaustion. Trials involved a no-cooling control (CON), precooling (PRE) or cooling during exercise (DUR). Each intermittent sprint protocol consisted of varied periods of passive rest, maximal sprinting and active recovery.Both PRE and DUR cooling strategies improved the ability of the athletes to repeatedly perform high-intensity sprints, with times to exhaustion (TTE), whereas during the CON trial, athletes demonstrated a reduction in the total number of sprints and TTE (47.2 (10.8), 52.8 (5.8) and 36.2 (9.6) min for CON, PRE and DUR, respectively). Core temperature was significantly higher for CON (37.3 degrees C (0.3 degrees C)) when compared with both PRE and DUR (36.5 degrees C (0.6 degrees C) and 37.0 degrees C (0.5 degrees C), respectively, p0.01). Ratings of perceived exertion and thermal sensation upon exhaustion or completion were not different.Athletes with tetraplegia should use a precooling or during-exercise cooling strategy specific to the characteristics of their sport when exercising in hot conditions.

In this study, we examined the effects of different work:rest durations during 20 min intermittent treadmill running and subsequent performance. Nine males (mean age 25.8 years, s = 6.8; body mass 73.9 kg, s = 8.8; stature 1.75 m, s = 0.05; VO(2max) 55.5 ml x kg(-1) x min(-1), s = 5.8) undertook repeated sprints at 120% of the speed at which VO(2max) was attained interspersed with passive recovery. The work:rest ratio was constant (1:1.5) with trials involving either short (6:9 s) or long (24:36 s) work:rest exercise protocols (total exercise time 8 min). Each trial was followed by a performance run to volitional exhaustion at the same running speed. Testing order was randomized and counterbalanced. Heart rate, oxygen consumption, respiratory exchange ratio, and blood glucose were similar between trials (P0.05). Blood lactate concentration was greater during the long than the short exercise protocol (P0.05), whereas blood pH was lower during the long than the short exercise protocol (7.28, s = 0.11 and 7.30, s = 0.03 at 20 min, respectively; P0.05). Perceptions of effort were greater throughout exercise for the long than the short exercise protocol (16.6, s = 1.4 and 15.1, s = 1.6 at 20 min, respectively; P0.05) and correlated with blood lactate (r = 0.43) and bicarbonate concentrations (r = 0.59; P0.05). Although blood lactate concentration at 20 min was related to performance time (r = - 0.56; P0.05), no differences were observed between trials for time to exhaustion (short exercise protocol: 95.8 s, s = 30.0; long exercise protocol: 92.0 s, s = 37.1) or physiological responses at exhaustion (P0.05). Our results demonstrate that 20 min of intermittent exercise involving a long work:rest duration elicits greater metabolic and perceptual strain than intermittent exercise undertaken with a short work:rest duration but does not affect subsequent run time to exhaustion.

The main aim of this study was to determine whether the use of an imposed or freely chosen crank rate would influence submaximal and peak physiological responses during arm crank ergometry. Fifteen physically active men participated in the study. Their mean age, height, and body mass were 25.9 (s = 6.2) years, 1.80 (s = 0.10) m, and 78.4 (s = 6.1) kg, respectively. The participants performed two incremental peak oxygen consumption (VO(2peak)) tests using an electronically braked ergometer. One test was performed using an imposed crank rate of 80 rev x min(-1), whereas in the other the participants used spontaneously chosen crank rates. The order in which the tests were performed was randomized, and they were separated by at least 2 days. Respiratory data were collected using an on-line gas analysis system, and fingertip capillary blood samples ( approximately 20 microl) were collected for the determination of blood lactate concentration. Heart rate was also recorded throughout the tests. Time to exhaustion was measured and peak aerobic power calculated. Submaximal data were analysed using separate two-way repeated-measures analyses of variance, while differences in peak values were analysed using separate paired t-tests. Variations in spontaneously chosen crank rate were assessed using a one-way analysis of variance with repeated measures. Agreement between the crank rate strategies for the assessment of peak values was examined by calculating intra-class correlation coefficients (ICC) and 95% limits of agreement (95% LoA). While considerable between-participant variations in spontaneously chosen crank rate were observed, the mean value was not different (P0.05) from the imposed crank rate of 80 rev x min(-1) at any point. No differences (P0.05) were observed for submaximal data between crank strategies. Furthermore, mean peak minute power [158 (s = 20) vs. 158 (s = 18) W], time to exhaustion [739 (s = 118) vs. 727 (s = 111) s], and VO(2peak)[3.09 (s = 0.38) vs. 3.04 (s = 0.34) l x min(-1)] were similar for the imposed and spontaneously chosen crank rates, respectively. However, the agreement for the assessment of VO(2peak) (ICC = 0.78; 95% LoA = 0.04 +/- 0.50 l x min(-1)) between the cranking strategies was considered unacceptable. Our results suggest that either an imposed or spontaneously chosen crank rate strategy can be used to examine physiological responses during arm crank ergometry, although it is recommended that the two crank strategies should not be used interchangeably.

This study examined the effects of different work - rest durations during 40 min intermittent treadmill exercise and subsequent running performance. Eight males (mean +/- s: age 24.3 +/- 2.0 years, body mass 79.4 +/- 7.0 kg, height 1.77 +/- 0.05 m) undertook intermittent exercise involving repeated sprints at 120% of the speed at which maximal oxygen uptake (nu-VO2max) was attained with passive recovery between each one. The work - rest ratio was constant at 1:1.5 with trials involving short (6:9 s), medium (12:18 s) or long (24:36 s) work - rest durations. Each trial was followed by a performance run to volitional exhaustion at 150% nu-VO2max. After 40 min, mean exercise intensity was greater during the long (68.4 +/- 9.3%) than the short work - rest trial (54.9 +/- 8.1% VO2max; P0.05). Blood lactate concentration at 10 min was higher in the long and medium than in the short work - rest trial (6.1 +/- 0.8, 5.2 +/- 0.9, 4.5 +/- 1.3 mmol x l(-1), respectively; P0.05). The respiratory exchange ratio was consistently higher during the long than during the medium and short work - rest trials (P0.05). Plasma glucose concentration was higher in the long and medium than in the short work - rest trial after 40 min of exercise (5.6 +/- 0.1, 6.6 +/- 0.2 and 5.3 +/- 0.5 mmol x l(-1), respectively; P0.05). No differences were observed between trials for performance time (72.7 +/- 14.9, 63.2 +/- 13.2, 57.6 +/- 13.5 s for the short, medium and long work - rest trial, respectively; P = 0.17), although a relationship between performance time and 40 min plasma glucose was observed (P0.05). The results show that 40 min of intermittent exercise involving long and medium work - rest durations elicits greater physiological strain and carbohydrate utilization than the same amount of intermittent exercise undertaken with a short work-rest duration.

PRICE, M., P. MOSS, and S. RANCE. Effects of Sodium Bicarbonate Ingestion on Prolonged Intermittent Exercise. Med. Sci. Sports Exerc., Vol. 35, No. 8, pp. 1303–1308, 2003. Purpose: The aim of this study was to determine the effects of sodium bicarbonate ingestion on prolonged intermittent exercise and performance. Methods: Eight healthy male subjects (mean SD: age 25.4 6.4 yr, mass 70.9 5.1 kg, height 179 7 cm, V u O2max 4.21 0.51 L·min 1 ) volunteered for the study, which had received ethical approval. Subjects undertook two 30-min intermittent cycling trials (repeated 3-min blocks; 90 s at 40% V u O2max ,6 0 sa t 60% Vu O2max, 14-s maximal sprint, 16-s rest) after ingestion of either sodium bicarbonate (NaHCO3; 0.3 g·kg 1 ) or sodium chloride (NaCl; 0.045 g·kg 1 ). Expired air, blood lactate (BLa), bicarbonate (HCO3 ), and pH were measured at rest, 30 and 60 min postingestion, and during the 40% V u O2max component of exercise (4, 10, 16, and 29 min). Results: After ingestion, pH increased from rest to 7.46 0.03 and 7.40 0.01 for NaHCO3 and NaCl, respectively (main effect for time and trial; P 0.05). Values decreased at 15 min of exercise to 7.30 0.07 and 7.21 0.06, respectively, remaining at similar levels until the end of exercise. BLa peaked at 15 min (12.03 4.31 and 10.00 2.58 mmol·L 1 , for NaHCO3 and NaCl, respectively; P 0.05) remaining elevated until the end of exercise (P 0.05). Peak power expressed relative to sprint 1 demonstrated a significant main effect between trials ( P 0.05). Sprint 2 increased by 11.5 5% and 1.8 9.5% for NaHCO3 and NaCl, respectively. During NaHCO3, sprint 8 remained similar to sprint 1 (0.2 17%), whereas a decrease was observed during NaCl (10.0 16.0%). Conclusion: The results of this study suggest that ingestion of NaHCO3 improves sprint performance during prolonged intermittent cycling. Key Words: BLOOD LACTATE, PH, ALKALOSIS, PEAK POWER, PERFORMANCE, RPE

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.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.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; P0.05). Upper-arm skin temperature was higher for the TP when compared with the HP and LP between 30 and 60 min (P0.05). Back skin temperature was higher for the TP when compared with the HP and LP between 45 and 60 min (P0.05). 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 (P0.05). Heat storage was greatest for the TP athletes at the end of exercise and remained elevated throughout recovery (P0.05).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.

The aim of this study was to assess the influence of three imposed crank rates on the attainment of peak oxygen consumption (VO2peak) and other physiological responses during incremental arm crank ergometry. Twenty physically active, although non-specifically trained, males volunteered for the study. They completed an exercise protocol using an electrically braked arm ergometer (Lode Angio, Groningen, Netherlands) at crank rates of 60, 70 and 80 rev x min(-1). The order of tests was randomized and they were separated by at least 2 days. Peak VO2 was significantly higher (P0.05) at 70 and 80 rev x min(-1) than at 60 rev x min(-1). Peak ventilation volume increased as a function of crank rate and was higher (P0.05) at 80 than at 60 rev x min(-1). Peak heart rate was higher (P0.05) at 70 and 80 rev x min(-1) than at 60 rev x min(-1). Furthermore, 70 and 80 rev x min(-1) resulted in an extended test time compared with 60 rev x min(-1). The greater physiological responses observed during the tests at the two faster crank rates might have been the result of a postponement of acute localized neuromuscular fatigue, allowing for more work to be completed. We recommend, therefore, that an imposed crank rate between 70 and 80 rev x min(-1) should be used to elicit VO2peak and other physiological responses in arm crank ergometry.

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

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 (p0.05). 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.

Head injuries in skiing have been a cause for concern due to the high incidence of injury particularly in young people. Furthermore, head trauma is the leading cause of death overall in skiing. Encouraging individuals to wear helmets can be problematic, especially since helmets are not compulsory in many resorts, are an additional expense and not seen as a necessity. The aim was (1) To synthesise information regarding head injuries and helmet use in young people. (2) To make a recommendation for the appropriateness of helmets use. Following ethical approval and informed consent, 101 responses were gathered from an electronic survey. This was administered to secondary schools across England which organise ski trips to identify helmet use. Electronic databases were searched for articles dating back 15 years and synthesised with grey literature as a narrative review to inform current concepts on helmet use in young people. The pooled narrative findings from literature suggest helmet use has reduced the number and severity of injuries to the head. The overall consensus is for helmets to be recommended, especially in the young. From 101 secondary schools surveyed, 96% of teachers expect young people to wear helmets whilst skiing. Discussion: The compulsory wearing of helmets in several resorts has helped to increase the awareness and importance of helmet use. A potential impact on not wearing a helmet is the concern that holiday insurance could be invalidated if injured. One British insurer now stipulates for the mandatory wearing of helmets within their policy. Findings show helmet use has been associated with a reduced risk of head injuries and the International Ski Federation recommends that all skiers regardless of ability and age use helmets. Ski helmets should be included within the ski rental package to decrease financial barriers.

Sprint tests are frequently used to evaluate between-subject differences and can provide a valuable insight into performance capacity. The present study determined the reproducibility of peak and mean power output during upper-body sprints. After familiarization 25 men (mean [+/- SD] age 29 [6] years, body mass 82.8 [12.7] kg and height 1.76 [0.05] m) completed 2 20-second upper-body sprint tests using an adapted cycle ergometer. Mean (+/- SD) values of all power (uncorrected and corrected) measurements achieved during the 2 tests were checked for systematic bias using separate paired t-tests. Test-retest reproducibility was examined using coefficients of variation and single-measure intraclass correlation coefficients, as well as an assessment of the typical (random) error and the 95% limits of agreement. The value of corrected peak power (628 [167] W) was higher (p0.05) compared with the uncorrected value (509 [109] W). Values of corrected (465 [95] W) and uncorrected (444 [87] W) mean power were similar (p0.05). The mean bias value for all power parameters equated to less than +/-1% of the absolute values of power measured. Intraclass correlation coefficients for all data sets ranged from 0.97 to 0.98. Coefficients of variation for uncorrected and corrected values of peak power were 2.8 and 4.5%, while corresponding values for mean power were 2.9 and 3.2%, respectively. The reproducibility of all power indices was below 5%. The results of this study indicate that both uncorrected and corrected measurements of peak power output and mean power output can be used to assess performance during sprint arm ergometry.