B.A. Wall

Current hydration guidelines are erroneous: dehydration does not impair exercise performance in the heat

Background Laboratory studies that support the hydration guidelines of leading governing bodies have shown that dehydration to only −2% of body mass can lead to increase in body temperature and heart rate during exercise, and decrease in performance. These studies, however, have been conducted in relatively windless environments (ie, wind speed <12.9 km/h), without participants being blinded to their hydration status. Aim To investigate the effect of blinded hydration status on cycling time-trial performance in the heat with ecologically valid facing wind speed conditions. Methods During three experimental trials, 10 cyclists were dehydrated to −3% body mass by performing 2 h of submaximal exercise (walking and cycling) in the heat, before being reinfused with saline to replace 100%, 33% or 0% of fluid losses, leaving them 0%, −2% or −3% hypohydrated, respectively. Participants then completed a 25 km time trial in the heat (33°C, 40% relative humidity; wind speed 32 km/h) during which their starting hydration status was maintained by infusing saline at a rate equal to their sweat rate. The treatment was participant-blinded and the order was randomised. Completion time, power output, heart rate, rectal temperature and perceptual variables were measured. Results While rectal temperature was higher beyond 17 km of the time trial in the −3% vs 0% conditions (38.9±0.3°C vs 38.6±0.3°C; p<0.05), no other differences between trials were shown. Conclusion When well-trained cyclists performed a 25 km cycling time trial under ecologically valid conditions and were blinded to their hydration status, performance, physiological and perceptual variables were not different between trials. These data do not support the residing basis behind many of the current hydration guidelines.

A phase III clinical trial of exercise modalities on treatment side-effects in men receiving therapy for prostate cancer

BackgroundAndrogen deprivation therapy (ADT) is accompanied by a number of adverse side effects including reduced bone mass and increased risk for fracture, reduced lean mass and muscle strength, mood disturbance and increased fat mass compromising physical functioning, independence, and quality of life. The purpose of this investigation is to examine the effects of long term exercise on reversing musculoskeletal-related side effects, and cardiovascular and diabetes risk factors in men receiving androgen deprivation for their prostate cancer. Specifically, we aim to investigate the effects of a 12-month exercise program designed to load the musculoskeletal system and reduce cardiovascular and diabetes disease progression on the following primary endpoints: 1) bone mineral density; 2) cardiorespiratory function and maximal oxygen capacity; 3) body composition (lean mass and fat mass); 4) blood pressure and cardiovascular function; 5) lipids and glycemic control; and 6) quality of life and psychological distress.Methods/DesignMulti-site randomized controlled trial of 195 men (65 subjects per arm) undergoing treatment for prostate cancer involving ADT in the cities of Perth and Brisbane in Australia. Participants will be randomized to (1) resistance/impact loading exercise, (2) resistance/cardiovascular exercise groups and (3) usual care/delayed exercise. Participants will then undergo progressive training for 12 months. Measurements for primary and secondary endpoints will take place at baseline, 6 and 12 months (end of the intervention).DiscussionThe principal outcome of this project will be the determination of the strength of effect of exercise on the well established musculoskeletal, cardiovascular and insulin metabolism side effects of androgen deprivation in prostate cancer patients. As this project is much longer term than previous investigations in the area of exercise and cancer, we will gain knowledge as to the continuing effects of exercise in this patient population specifically targeting bone density, cardiovascular function, lean and fat mass, physical function and falls risk as primary study endpoints. In terms of advancement of prostate cancer care, we expect dissemination of the knowledge gained from this project to reduce fracture risk, improve physical and functional ability, quality of life and ultimately survival rate in this population.Clinical Trial RegistryA Phase III clinical trial of exercise modalities on treatment side-effects in men receiving therapy for prostate cancer; ACTRN12609000200280

Effects of Different Exercise Modalities on Fatigue in Prostate Cancer Patients Undergoing Androgen Deprivation Therapy: A Year-long Randomised Controlled Trial

BACKGROUND Physical exercise mitigates fatigue during androgen deprivation therapy (ADT); however, the effects of different exercise prescriptions are unknown. OBJECTIVES To determine the long-term effects of different exercise modes on fatigue in prostate cancer patients undergoing ADT. DESIGN, SETTING, AND PARTICIPANTS Between 2009 and 2012, 163 prostate cancer patients aged 43-90 y on ADT were randomised to exercise targeting the musculoskeletal system (impact loading+resistance training; ILRT; n=58), the cardiovascular and muscular systems (aerobic+resistance training; ART; n=54), or to usual care/delayed exercise (DEL; n=51) for 12 mo across university-affiliated exercise clinics in Australia. INTERVENTION Supervised ILRT for 12 mo, supervised ART for 6 mo followed by a 6-mo home program, and DEL received a printed booklet on exercise information for 6 mo followed by 6-mo stationary cycling exercise. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Fatigue was assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 36 and vitality using the Short Form-36. Analysis of variance was used to compare outcomes for groups at 6 mo and 12 mo. RESULTS AND LIMITATIONS Fatigue was reduced (p=0.005) in ILRT at 6 mo and 12 mo (∼5 points), and in ART (p=0.005) and DEL (p=0.022) at 12 mo. Similarly, vitality increased for all groups (p≤0.001) at 12 mo (∼4 points). Those with the highest levels of fatigue and lowest vitality improved the most with exercise (ptrend<0.001). A limitation was inclusion of mostly well-functioning individuals. CONCLUSIONS Different exercise modes have comparable effects on reducing fatigue and enhancing vitality during ADT. Patients with the highest levels of fatigue and lowest vitality had the greatest benefits. PATIENT SUMMARY We compared the effects of different exercise modes on fatigue in men on androgen deprivation therapy. All exercise programs reduced fatigue and enhanced vitality. We conclude that undertaking some form of exercise will help reduce fatigue, especially in those who are the most fatigued.

Influence of starting strategy on cycling time trial performance in the heat

The purpose of this study was to determine the influence of starting strategy on time trial performance in the heat. Eleven endurance trained male cyclists (30+/-5 years, 79.5+/-4.6 kg, VO(2max) 58.5+/-5.0 ml x kg x (-1) min(-1)) performed four 20-km time trials in the heat (32.7+/-0.7 degrees C and 55% relative humidity). The first time trial was completed at a self-selected pace (SPTT). During the following time trials, subjects performed the initial 2.5-km at power outputs 10% above (10% ATT), 10% below (10% BTT) or equal (ETT) to that of the average power during the initial 2.5-km of the self-selected trial; the remaining 17.5-km was self-paced. Throughout each time trial, power output, rectal temperature, skin temperature, heat storage, pain intensity and thermal sensation were taken. Despite significantly (P<0.05) greater power outputs for 10% BTT (273+/-45W) compared with the ETT (267+/-48W) and 10% ATT (265+/-41W) during the final 17.5-km, overall 20-km performance time was not significantly different amongst trials. There were no differences in any of the other measured variables between trials. These data show that varying starting power by +/-10% did not affect 20 km time trial performance in the heat.

Exercise Improves V˙O2max and Body Composition in Androgen Deprivation Therapy–treated Prostate Cancer Patients:

Introduction Prostate cancer is the most common cancer in men, and patients treated with androgen deprivation therapy (ADT) experience unfavorable changes in body composition and associated metabolic complications, which can increase the risk of cardiovascular disease. We examined the effect of a 6-month program of aerobic and resistance exercise aimed at improving body composition and cardiorespiratory health in this population. Methods Ninety-seven men (43–90 yr) with localized prostate cancer receiving ADT were randomized to either exercise (EX, n = 50) or usual care (CON, n = 47). Supervised exercise was undertaken twice weekly at moderate to high intensity. Measures of cardiorespiratory capacity (V˙O2max), resting metabolic rate, central blood pressure, hemodynamic variables, blood markers, and body composition were assessed. Results There was a significant group–time interaction present for V˙O2max (P = 0.033) with a treatment effect for EX of 0.11 L·min−1 (95% confidence interval [CI] = 0.04–0.19) (relative to body mass = 1.3 mL·kg−1·min−1, 95% CI = 0.3–2.3) and fat oxidation (P = 0.037) of 12.0 mg·min−1 (95% CI = 2.3–21.7). Similarly, there was a significant improvement in glucose (P < 0.001) for EX of −0.5 mmol·L−1 (95% CI = −0.8 to −0.3), with no change in prostate-specific antigen or testosterone as a result of exercise. Body composition was enhanced for EX with adjusted mean differences in lean mass (P = 0.015) of 0.8 kg (95% CI = 0.3–1.3), total fat mass (P = 0.020) of −1.1 kg (95% CI = −1.8 to −0.5), and trunk fat mass (P < 0.001) of −1.0 kg (95% CI = −1.4 to −0.6). Conclusion A 6-month combined aerobic and resistance exercise program has a significant favorable effect on cardiorespiratory capacity, resting fat oxidation, glucose, and body composition despite the adverse effects of hormone suppression. Combined aerobic and resistance training should be considered a key adjuvant component in men undergoing ADT for the treatment of prostate cancer.INTRODUCTION: Prostate cancer is the most common cancer in men and patients treated with androgen deprivation therapy (ADT) experience unfavourbale changes in body composition and associated metabolic complications, which can increase the risk of cardiovascular disease. We examined the effect of a 6-month program of aerobic and resistance exercise aimed at improving body composition and cardiorespiratory health in this population. METHODS: Ninety-seven men (43-90 years) with localized prostate cancer receiving ADT were randomized to either exercise (EX, n=50) or usual care (CON, n=47). Supervised exercise was undertaken twice-weekly at moderate-to-high intensity. Measures of cardiorespiratory capacity (V[Combining Dot Above]O2max), resting metabolic rate, central blood pressure, hemodynamic variables, blood markers, and body composition were assessed. RESULTS: There was a significant group by time interaction present for V[Combining Dot Above]O2max (p=0.033) with a treatment effect for EX of 0.11 (95% CI, 0.04-0.19) L.min [relative to body mass 1.3 (95% CI, 0.3-2.3) ml.kg.min], and fat oxidation (p=0.037) of 12.0 (95% CI, 2.3-21.7) mg.min. Similarly, there was a significant improvement in glucose (p<0.001) for EX of -0.5 (95% CI, -0.8 to -0.3) mmol/L, with no change in PSA or testosterone as a result of exercise. Body composition was enhanced for EX with adjusted mean differences in lean mass (p=0.015) of 0.8 (95% CI, 0.3-1.3) kg, total fat mass (p=0.020) of -1.1 (95% CI, -1.8 to -0.5) kg, and trunk fat mass (p<0.001) of -1.0 (95% CI, -1.4 to -0.6) kg. CONCLUSION: A 6-month combined aerobic and resistance exercise program has a significant favorable impact on cardiorespiratory capacity, resting fat oxidation, glucose and body composition despite the adverse effects of hormone suppression. Combined aerobic and resistance training should be considered a key adjuvant component in men undergoing ADT for the treatment of prostate cancer.

Reduced Cardiovascular Capacity and Resting Metabolic Rate in Men with Prostate Cancer Undergoing Androgen Deprivation: A Comprehensive Cross-Sectional Investigation

Objectives. To investigate if androgen deprivation therapy exposure is associated with additional risk factors for cardiovascular disease and metabolic treatment-related toxicities. Methods. One hundred and seven men (42–89 years) with prostate cancer undergoing androgen deprivation therapy completed a maximal graded objective exercise test to determine maximal oxygen uptake, assessments for resting metabolic rate, body composition, blood pressure and arterial stiffness, and blood biomarker analysis. A cross-sectional analysis was undertaken to investigate the potential impact of therapy exposure with participants stratified into two groups according to duration of androgen deprivation therapy (<3 months and ≥3 months). Results. Maximal oxygen uptake (26.1 ± 6.0 mL/kg/min versus 23.2 ± 5.8 mL/kg/min, p = 0.020) and resting metabolic rate (1795 ± 256 kcal/d versus 1647 ± 236 kcal/d, p = 0.005) were significantly higher in those with shorter exposure to androgen deprivation. There were no differences between groups for peripheral and central blood pressure, arterial stiffness, or metabolic profile. Conclusion. Three months or longer exposure to androgen deprivation therapy was associated with reduced cardiorespiratory capacity and resting metabolic rate, but not in a range of blood biomarkers. These findings suggest that prolonged exposure to androgen deprivation therapy is associated with negative alterations in cardiovascular outcomes. Trial registry is: ACTRN12609000200280.

Maximal exercise testing of men with prostate cancer being treated with androgen deprivation therapy

UNLABELLED Exercise is being increasingly established as a key adjuvant therapy in clinical oncology. As research has demonstrated the beneficial effect of exercise for cancer management, a growing number of patients with cancer are undertaking structured exercise programs. PURPOSE This study aimed to determine the safety and feasibility of formal exercise testing in clinical settings as it is becoming increasingly used as a screening tool and for exercise prescription purposes. METHODS One hundred and twelve patients with prostate cancer undergoing androgen deprivation therapy (ADT) took part in a physician-supervised multistage maximal stress test (Bruce protocol). Sixty patients had been on ADT for <3 months (acute), whereas 52 had been on ADT for >3 months (chronic). RESULTS Of these men, 85% were able to meet the criteria for the attainment of V˙O2max, whereas three positive tests (3.2%) were observed. The three participants who recorded a positive stress test underwent further medical examination and were subsequently cleared of clinically significant cardiovascular disease. Apart from the relatively low V˙O2max (24.7 ± 6.0 mL·kg·min, 10th-15th percentile), compared with normative data in healthy age-matched controls, the cardiovascular response to exercise was similar in this cancer population. Moreover, treatment duration did not seem to influence cardiovascular responses to exercise. This early evidence suggests that risk of adverse events during maximal exercise testing is relatively low in this population and certainly no higher than that in ages-matched, apparently healthy individuals. CONCLUSIONS Maximal exercise testing was demonstrated to be feasible and safe, providing a direct assessment of V˙O2max. The relatively low number of positive tests in this study suggests that the risk of adverse events is relatively low in this population and certainly no higher than that in age-matched, apparently healthy individuals.

Exercise Improves V[Combining Dot Above]O 2max and Body Composition in ADT-treated Prostate Cancer Patients

Introduction Prostate cancer is the most common cancer in men, and patients treated with androgen deprivation therapy (ADT) experience unfavorable changes in body composition and associated metabolic complications, which can increase the risk of cardiovascular disease. We examined the effect of a 6-month program of aerobic and resistance exercise aimed at improving body composition and cardiorespiratory health in this population. Methods Ninety-seven men (43–90 yr) with localized prostate cancer receiving ADT were randomized to either exercise (EX, n = 50) or usual care (CON, n = 47). Supervised exercise was undertaken twice weekly at moderate to high intensity. Measures of cardiorespiratory capacity (V˙O2max), resting metabolic rate, central blood pressure, hemodynamic variables, blood markers, and body composition were assessed. Results There was a significant group–time interaction present for V˙O2max (P = 0.033) with a treatment effect for EX of 0.11 L·min−1 (95% confidence interval [CI] = 0.04–0.19) (relative to body mass = 1.3 mL·kg−1·min−1, 95% CI = 0.3–2.3) and fat oxidation (P = 0.037) of 12.0 mg·min−1 (95% CI = 2.3–21.7). Similarly, there was a significant improvement in glucose (P < 0.001) for EX of −0.5 mmol·L−1 (95% CI = −0.8 to −0.3), with no change in prostate-specific antigen or testosterone as a result of exercise. Body composition was enhanced for EX with adjusted mean differences in lean mass (P = 0.015) of 0.8 kg (95% CI = 0.3–1.3), total fat mass (P = 0.020) of −1.1 kg (95% CI = −1.8 to −0.5), and trunk fat mass (P < 0.001) of −1.0 kg (95% CI = −1.4 to −0.6). Conclusion A 6-month combined aerobic and resistance exercise program has a significant favorable effect on cardiorespiratory capacity, resting fat oxidation, glucose, and body composition despite the adverse effects of hormone suppression. Combined aerobic and resistance training should be considered a key adjuvant component in men undergoing ADT for the treatment of prostate cancer.INTRODUCTION: Prostate cancer is the most common cancer in men and patients treated with androgen deprivation therapy (ADT) experience unfavourbale changes in body composition and associated metabolic complications, which can increase the risk of cardiovascular disease. We examined the effect of a 6-month program of aerobic and resistance exercise aimed at improving body composition and cardiorespiratory health in this population. METHODS: Ninety-seven men (43-90 years) with localized prostate cancer receiving ADT were randomized to either exercise (EX, n=50) or usual care (CON, n=47). Supervised exercise was undertaken twice-weekly at moderate-to-high intensity. Measures of cardiorespiratory capacity (V[Combining Dot Above]O2max), resting metabolic rate, central blood pressure, hemodynamic variables, blood markers, and body composition were assessed. RESULTS: There was a significant group by time interaction present for V[Combining Dot Above]O2max (p=0.033) with a treatment effect for EX of 0.11 (95% CI, 0.04-0.19) L.min [relative to body mass 1.3 (95% CI, 0.3-2.3) ml.kg.min], and fat oxidation (p=0.037) of 12.0 (95% CI, 2.3-21.7) mg.min. Similarly, there was a significant improvement in glucose (p<0.001) for EX of -0.5 (95% CI, -0.8 to -0.3) mmol/L, with no change in PSA or testosterone as a result of exercise. Body composition was enhanced for EX with adjusted mean differences in lean mass (p=0.015) of 0.8 (95% CI, 0.3-1.3) kg, total fat mass (p=0.020) of -1.1 (95% CI, -1.8 to -0.5) kg, and trunk fat mass (p<0.001) of -1.0 (95% CI, -1.4 to -0.6) kg. CONCLUSION: A 6-month combined aerobic and resistance exercise program has a significant favorable impact on cardiorespiratory capacity, resting fat oxidation, glucose and body composition despite the adverse effects of hormone suppression. Combined aerobic and resistance training should be considered a key adjuvant component in men undergoing ADT for the treatment of prostate cancer.

Recovery following an Ironman triathlon: A case study

Abstract Completion of an Ironman triathlon results in muscle damage, indicated by reductions in muscle function and muscle soreness. However, the time course of recovery from this damage has received little attention. The purpose of this case study was to examine the time course of changes in blood markers of muscle damage and inflammation, muscle function, muscle soreness, and economy of motion following an Ironman event. An experienced well-trained male triathlete aged 35 years completed the Western Australian Ironman triathlon in 11 h 38 min 41 s (winners time: 8 h 3 min 56 s). Before and on several occasions in the 15 days after the event, the participant performed an incremental cycling test to exhaustion, running economy test at 12 km · h−1 (2% incline), maximal isometric knee flexion and extension at 90° knee flexion, and maximal squat and countermovement jumps. Venous blood samples and muscle soreness were also assessed. Maximal oxygen consumption, efficiency of motion, maximal muscle strength, and jump performance were all markedly reduced (4.5–54%) following the event, but returned to baseline within 15, 8, 2, and 8 days following the event, respectively. Muscle soreness and blood markers peaked 2–24 h after the race but returned to baseline within 8 days. In conclusion, although the Ironman triathlon induces marked muscle damage, a trained triathlete recovered almost completely within approximately one week, without the use of any therapeutic interventions after the event.

Androgen-Deprivation Therapy and Cardiovascular Disease Risk – The Role of Exercise in Prostate Cancer Treatment

Reduced levels of physical activity and increased levels of fatigue are commonly reported in prostate cancer patients treated with androgen-deprivation therapy (ADT) (1) that in turn reduces functional capacity. Reductions are seen in cardiorespiratory endurance, upper and lower body strength and endurance, and physical components of quality of life (1–3), which lead to inhibiting activities of daily living. In addition to these well-established side effects, cardiovascular disease (CVD) risk is now being increasingly associated with ADT (4, 5). Keating et al. (6) report ADT use is associated with higher risks of incident diabetes, coronary heart disease, acute myocardial infarction, and sudden cardiac death. The increasing body of literature supports an earlier report indicating that CVD is the most common form of mortality in men with prostate cancer, and not the actual cancer itself (7). Exercise has been shown to be effective for improving surgical outcomes, reducing symptom experience, managing side effects, improving psychological health, maintaining physical function, and reducing fat gain and muscle and bone loss in cancer patients (8) and hence has the potential to reduce CVD risk factors. Studies in the past have used aerobic exercise (9), resistance exercise (9, 10), or a combination of aerobic and resistance exercise (11). Exercise programs have also differed in method of delivery with some home based (12) while others are group based in a clinic setting (11, 13) making comparisons as to the best treatment mode of exercise difficult.