Addition of aerobic training to conventional rehabilitation after hip fracture: a randomized, controlled, pilot feasibility study

Objectives: To determine the feasibility and safety of aerobic training with an arm crank ergometer and its effectiveness in improving functional capacity and gait in patients with recent hip fracture. Design: Randomized, controlled, assessor-blinded pilot study, with intention-to-treat analysis. Setting: Inpatients, rehabilitation department. Subjects: 40 patients with hip fracture surgically treated. Interventions: Training group performed aerobic exercise with an arm crank ergometer (15 sessions, 30 minutes/day) at an intensity of 64% to 76% of maximum heart rate, in addition to conventional inpatient rehabilitation. Main measures: Primary outcome was the feasibility (including eligibility rate, recruitment rate, number of drop-outs and adverse events, adherence). Secondary measures were the Timed Up and Go test, ability to walk independently, muscle torque of knee extensors of fractured and non-fractured leg, Functional Independence Measure. Results: Mostly due to pre-existing disability and fracture type, only 40/301 (13%) patients were eligible (age 84.6 ± 7.6 years, 75% female); all agreed to participate and 90% completed the trial, without adverse events. Adherence to aerobic exercise was good, with high attendance at sessions (93%), a strong compliance to exercise duration (95%) but lower compliance to the prescribed intensity (73%). After the program, more patients were able to walk independently in the training group ( n = 18) compared to control ( n = 13) ( P < 0.05). Also the muscle torque of fractured leg knee extensors was higher in the training group ( P < 0.05). Conclusion: Aerobic training in addition to conventional rehabilitation after a hip fracture is feasible and safe and it was effective in improving gait performance and strength of fractured leg. Trial registration: NCT04025866.

Spirulina supplementation improves oxygen uptake in arm cycling exercise

Purpose Spirulina has previously been reported to improve high-intensity exercise performance and hemoglobin. However, spirulina’s effect on arm cycling exercise has yet to be investigated. The purpose of this study was to investigate the responses of spirulina supplementation on hemoglobin and on oxygen uptake, RER and HR during seated arm cycling exercise. Methods In a double-blinded randomized crossover design, eleven males untrained in arm cycling ingested 6 g/day of spirulina or placebo for seven days. Seated on the Arm Crank Ergometer, each participant performed a baseline V̇O2max test, and then after supplementation, 2 × 30-min submaximal exercise bouts corresponding to 55% of their V̇O2max, followed by an incremental test to fatigue. A seven-day wash-out period was required between conditions. Oxygen uptake, RER and HR were measured continuously during exercise and hemoglobin measured prior to exercise after both conditions. Results Spirulina significantly (p < 0.05) increased Hb in comparison to Placebo (144.1 g/l ± 10.5 Vs 154.5 g/l ± 6.9). After spirulina supplementation, during the 30-min exercise bouts, oxygen uptake and HR were significantly lower (2170 ml/min ± 173 Vs 2311 ml/min ± 189 and 154 bpm ± 14 Vs 149 bpm ± 17), RER was not significantly different. In comparison to placebo, Spirulina significantly increased oxygen uptake at time of fatigue (34.10 ml/min/kg ± 6.03 Vs 37.37 ml/min/kg ± 5.98). Time taken to fatigue was not different. Conclusion Spirulina supplementation significantly reduces oxygen uptake and HR during arm cycling submaximal exercise, allowing for an increased oxygen uptake during an incremental test to fatigue.

Physiological responses in males with and without spinal cord injury to recumbent synchronous versus seated asynchronous arm crank stress tests (Respuestas fisiológicas en hombres con y sin lesión medular al realizar pruebas de esfuerzo con ergómetros de

Introduction: Maximal oxygen uptake (VO2) may be one of the most important variables in the study of the responses of people with spinal cord injury (SCI) and without SCI to physical exercise. The results achieved during its assessment serve as a diagnostic and health indicator in clinical settings. Objective: this study aimed to investigate the physiological responses in males with and without SCI performing a maximal incremental test on an asynchronous arm crank ergometer (ACr) and on a recumbent synchronous handbike ergometer (HB). Methods: ten males with SCI and 11 able-bodied males (AB group) participated in this study. Two maximal graded exercise tests were performed, starting at 10 watts and increasing the workload by 10 watts every minute until exhaustion. Results: the AB group achieved lower workloads and absolute VO2 values than the SCI group during the HB test (all p < 0.05). The submaximal values of the relative VO2 peak and RER at workloads between 40-90 watts showed significant differences between SCI and AB on HB and ACr. Significant linear relationships between workload and relative VO2 peak were found during the HB test (p < 0.001). Conclusions: these findings demonstrate that there are different physiological responses between adults with and without SCI when performing maximal and submaximal arm-ergometry. Interestingly, higher VO2 peak and workloads were achieved by the SCI group. In addition, specific prediction equations derived from the current study can be used to calculate the relative VO2 peak in handbikers with and without SCI. Resumen. Introducción: el consumo de oxígeno (VO2) es una de las variables más importantes en el estudio de la respuesta al ejercicio en personas con y sin lesión medular (SCI; AB). Objetivo: en este estudio se analizaron las respuestas fisiológicas en hombres adultos con y sin SCI al realizar pruebas de esfuerzo máximas en un ergómetro de brazos asincrónico (ACr) en sedestación y en un ergómetro de brazos sincrónico (HB) en posición supina. Métodos: diez hombres con SCI y 11 sin SCI participaron en este estudio. Dos pruebas de esfuerzo gradual fueron realizadas por cada participante, iniciando a 10 watts e incrementando la carga 10 watts cada minuto. Resultados: el grupo sin SCI alcanzó cargas y VO2 menores que los participantes con SCI durante el test en HB (p < 0.05). Los valores submáximos para el VO2 relativo y el RER a cargas de 40-90 watts fueron estadísticamente diferentes entre los grupos en ambos tests. Se observó una correlación lineal entre las cargas de trabajo y el VO2 relativo durante el test en HB (p < 0.001). Conclusiones: los resultados obtenidos en este estudio demuestran que existen respuestas fisiológicas diferentes entre personas con y sin SCI cuando realizan pruebas de esfuerzo con cargas máximas y submáximas. Llamativamente, el grupo SCI alcanzó mayores cargas de trabajo y VO2 que los no SCI. Finalmente, se presentan dos ecuaciones específicas para obtener el VO2 de manera indirecta en personas con y sin SCI mediante el uso de un HB.

Perceptually regulated training does not influence the differentiated RPE response following 16-weeks of aerobic exercise in adults with spinal cord injury

This study investigated the effect of prolonged familiarisation with ratings of perceived exertion (RPE) on the peripheral (RPEP) and central (RPEC) RPE responses to moderate–vigorous exercise in adults with spinal cord injury (SCI). RPEP and RPEC characterise the exertion of the working musculature and cardiorespiratory systems, respectively. Nineteen participants (age, 41.4 ± 11.4 years; peak oxygen uptake, 19.2 ± 7.2 mL·kg−1·min−1) with chronic SCI were randomly assigned to RPE-guided (n = 11; EXP) or active control (n = 8; CON) groups. EXP performed 16-weeks of RPE-guided, supervised aerobic training for 20 min, twice weekly, at RPE 3–6 (Category-Ratio 10 scale). CON had access to the same exercise equipment but received no specific advice on their exercise-training regime. Participants completed a graded exercise test, using an arm crank ergometer at pre- and post-training to determine peak oxygen uptake, with RPEP and RPEC recorded every minute throughout tests. Sixteen weeks training did not improve peak oxygen uptake. RPE decreased post-training at 50% (p = 0.02) and 70% peak oxygen uptake (p = 0.03), though there was no effect of group at either intensity (p = 0.54, 0.42, respectively). At 70% peak oxygen uptake, RPEP was greater than RPEC (4.2 ± 1.7 vs 3.4 ± 1.8, p < 0.005). Training with RPE-guidance for 16 weeks had no additional effect on the differentiated RPE responses to moderate-vigorous exercise in adults with SCI. Novelty In adults with SCI, differentiated RPE responses were not different between those who did, and did not, perform 16 weeks of RPE-guided training. This challenges whether familiarisation with RPE is necessary to be an effective regulator of exercise intensity in this population.

Comparison of Aerobic Performance Testing Protocols in Elite Male Wheelchair Basketball Players

In wheelchair sports, aerobic performance is commonly assessed with the use of an arm crank ergometer (ACE), a wheelchair ergometer (WCE) or a wheelchair treadmill (WCT). There are different protocols to identify peak oxygen uptake in wheelchair sports; however, only a few protocols have been applied to evaluate these conditions in wheelchair basketball players. The purpose of this study was to compare physiological responses during maximal exercise testing with the use of ACE and WCT in wheelchair basketball players. Twelve elite male wheelchair basketball players participated in this study. The research was performed during a training camp of the Polish National Wheelchair Basketball Team. The study participants were divided into two functional categories: A (players with class 1.0 - 2.5) and B (players with class 3.0 - 4.5). Two main maximal exercise tests, i.e. wheelchair treadmill stress test (WCT test) and arm crank ergometer stress test (ACE test) were used to evaluate aerobic performance of the players. There were no statistically significant differences in aerobic tests between the players from both groups. The comparison of results achieved in two aerobic tests performed on WCT and ACE did not reveal any significant differences between the analyzed variables (peak heart rate (HRpeak), peak oxygen uptake (VO2peak), minute ventilation (VE), anaerobic threshold (AT), lactate concentration (LApeak), and a drop in lactate concentration (%LA)). Strong correlations between results achieved in WCT and ACE tests were found for VO2peak, VE and LApeak. The main conclusion of the study is that both WCT and ACE tests may be useful when determining aerobic capacity of wheelchair basketball players. Moreover, both protocols can be used by athletes regardless of their functional capabilities and types of impairment.

Ergogenic Effects of Caffeine Consumption in a 3-min All-Out Arm Crank Test in Paraplegic and Tetraplegic Compared With Able-Bodied Individuals

The aim of our study was to investigate the effect of caffeine supplementation on 3-min all-out arm crank exercise performance in paraplegic (P) and tetraplegic (T) compared with able-bodied (AB) participants. A placebo-controlled, randomized, crossover, and double-blind study design was chosen to investigate the differences between caffeine (CAF) and placebo (PLC). In total, 34 healthy, trained participants were tested. Seventeen were AB (median [minimum; maximum] VO2peak: 33.9 mL/min/kg [23.6; 57.6]), 10 were P (VO2peak: 34.4 mL/min/kg [19.5; 48.8]), and 7 were T (VO2peak: 13.6 mL/min/kg [8.6; 16.3]). All participants performed two 3-min all-out tests on an arm crank ergometer following the ingestion of either PLC or CAF. Power output parameters, plasma caffeine (PC), epinephrine (EPI), and norepinephrine (NOR) concentrations were assessed. CAF significantly increased average power over the first 30 s (p = .028) and 60 s (p = .005) in P, but not in T (p = .61; p = .87) nor in AB (p = .25; p = .44). Peak power was increased in the CAF trial in AB (+46 W) as well as in P (+21 W) but was not significantly different from PLC (AB: p = .10; P: p = .17). PC significantly increased in all groups (AB: p = .002; P: p = .005; T: p = .018) whereas EPI showed a significant increase only in AB (p = .002) and in P (p = .018). NOR increased significantly in AB (p = .018) but did not increase in the other groups. Caffeine seems to enhance short-duration exercise performance in P. In contrast, T showed a high interindividual variability and overall no ergogenic effect was detected in this group.