D R Taaffe

Edith Cowan University, Joondalup, Western Australia, Australia

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Publications (167)403.7 Total impact

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    ABSTRACT: The bone-specific physical activity questionnaire (BPAQ) accounts for activities that affect bone but has not been used in studies with older adults. Relationships exist between the BPAQ-derived physical activity and bone density in healthy middle-aged and older men but not men with prostate cancer. Disease-related treatments detrimental to bone should be considered when administering the BPAQ.
    07/2014;
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    ABSTRACT: Exercise is being increasingly established as a key adjuvant therapy in clinical oncology. As research has demonstrated the beneficial impact of exercise for cancer management, a growing number of cancer patients are undertaking structured exercise programs. 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. One hundred and twelve prostate cancer patients undergoing ADT took part in a physician supervised multistage maximal stress test (Bruce protocol). 60 patients had been on ADT <3 months (acute) whilst 52 had been on ADT for > 3months (chronic). Of these men, 85% were able to meet the criteria for the attainment of VO2max whilst three positive tests (3.2%) were observed. The three participants who recorded a positive stress test underwent further medical examination and subsequently cleared of clinically significant cardiovascular disease. Apart from the relatively low VO2max (24.7 ± 6.0 ml.kg.min:10-15th percentile), compared to normative data in healthy age-matched controls, the cardiovascular response to exercise was similar in this cancer population. Moreover, treatment duration did not appear 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 age-matched apparently healthy individuals. Maximal exercise testing was demonstrated to be feasible and safe providing a direct assessment of VO2max. The relatively low number of positive tests in this study suggests the risk of adverse events is relatively low in this population and certainly no higher than age-matched apparently healthy individuals.
    Medicine and science in sports and exercise 04/2014; · 4.48 Impact Factor
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    ABSTRACT: Despite being a critical survivorship care issue, there is a clear gap in current knowledge of the optimal treatment of sexual dysfunction in men with prostate cancer. There is sound theoretical rationale and emerging evidence that exercise may be an innovative therapy to counteract sexual dysfunction in men with prostate cancer. Furthermore, despite the multidimensional aetiology of sexual dysfunction, there is a paucity of research investigating the efficacy of integrated treatment models. Therefore, the purpose of this study is to: 1) examine the efficacy of exercise as a therapy to aid in the management of sexual dysfunction in men with prostate cancer; 2) determine if combining exercise and brief psychosexual intervention results in more pronounced improvements in sexual health; and 3) assess if any benefit of exercise and psychosexual intervention on sexual dysfunction is sustained long term.Methods/design: A three-arm, multi-site randomised controlled trial involving 240 prostate cancer survivors will be implemented. Participants will be randomised to: 1) 'Exercise' intervention; 2) 'Exercise + Psychosexual' intervention; or 3) 'Usual Care'. The Exercise group will receive a 6-month, group based, supervised resistance and aerobic exercise intervention. The Exercise + Psychosexual group will receive the same exercise intervention plus a brief psychosexual self-management intervention that addresses psychological and sexual well-being. The Usual Care group will maintain standard care for 6 months. Measurements for primary and secondary endpoints will take place at baseline, 6 months (post-intervention) and 1 year follow-up. The primary endpoint is sexual health and secondary endpoints include key factors associated with sexual health in men with prostate cancer. Sexual dysfunction is one of the most prevalent and distressing consequences of prostate cancer. Despite this, very little is known about the management of sexual dysfunction and current health care services do not adequately meet sexual health needs of survivors. This project will examine the potential role of exercise in the management of sexual dysfunction and evaluate a potential best-practice management approach by integrating pharmacological, physiological and psychological treatment modalities to address the complex and multifaceted aetiology of sexual dysfunction following cancer.Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12613001179729.
    BMC Cancer 03/2014; 14(1):199. · 3.33 Impact Factor
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    ABSTRACT: To determine if supervised exercise minimises treatment toxicity in prostate cancer patients initiating androgen deprivation therapy (ADT). This is the first study to date which has investigated the potential role of exercise in preventing ADT toxicity rather than recovering from established toxicities. Sixty-three men scheduled to receive ADT were randomly assigned to a 3-month supervised exercise program involving aerobic and resistance exercise sessions commenced within 10 days of their first ADT injection (n = 32) or usual care (n = 31). The primary outcome was body composition (lean and fat mass). Other study outcomes included bone mineral density, physical function, blood biomarkers of chronic disease risk and bone turnover, general and prostate cancer specific quality of life, fatigue and psychological distress. Outcomes were compared between groups using analysis of covariance adjusted for baseline values. Compared to usual care, a 3-month exercise program preserved appendicular lean mass (p=0.019) and prevented gains in whole body fat mass, trunk fat mass and percent fat with group differences of -1.4 kg (p=0.001), -0.9 kg (p=0.008) and -1.3% (p<0.001), respectively. Significant between-group differences were also observed favouring the exercise group for cardiovascular fitness (V02 peak 1.1 ml/kg/min, p=0.004), muscular strength (4.0-25.9 kg, p≤0.026), lower body function (-1.1 s, p<0.001), total cholesterol-to-HDL cholesterol ratio (-0.52, p=0.028), sexual function (15.2, p=0.028), fatigue (3.1, p=0.042), psychological distress (-2.2, p=0.045), social functioning (3.8, p=0.015) and mental health (3.6-3.8, p≤0.022). No significant group differences were observed for any other outcomes. Commencing a supervised exercise program involving aerobic and resistance exercise when initiating ADT significantly reduced treatment toxicity while improving social functioning and mental health. Concurrent prescription of supervised exercise when initiating ADT is therefore advised to minimise morbidity associated with severe hypogonadism.
    BJU International 01/2014; · 3.05 Impact Factor
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    ABSTRACT: Exercise may represent an effective adjunct therapy to current medical management strategies for maintaining functional independence and improving quality of life in cancer patients with bone metastatic disease. However, it has yet to be determined if there are any sustained effects following the completion of an exercise program by patients with bone metastases. The aim of this study is to determine whether a 3-month supervised resistance exercise program results in any sustained functional benefits in prostate and breast cancer patients with bone metastatic disease. Twenty men and women with bone metastatic disease secondary to prostate or breast cancer completed a 3-month supervised resistance exercise program followed by a 6-month observation period. Outcomes were assessed at baseline, post-exercise, and 6-month follow-up. Fourteen participants completed the follow-up observation period. Significant improvements in physical function (4-6 %), physical activity levels (~160 min/week), lean mass (3-4 %), and quality of life (5-7 %) were observed at the completion of the exercise program. At the 6-month follow-up, significant improvements in ambulation (4 %), physical activity level (~105 min/week), whole body lean mass (2 %), and quality of life (13 %) remained. An appropriately designed and supervised 3-month resistance exercise program may lead to significant improvements in functional ability, physical activity level, lean mass, and quality of life that remain 6 months after completion of the program in cancer patients with bone metastases. Future trials involving larger sample sizes are required to expand these preliminary findings.
    Supportive Care in Cancer 01/2014; · 2.09 Impact Factor
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    ABSTRACT: Sexual dysfunction is one of the most common, distressing and persistent adverse effects of prostate cancer treatment, and has a profound effect on quality of life for the patient and his partner. Current health-care provisions are inadequate to address the demand for the management of sexual dysfunction, with approximately half of prostate cancer survivors reporting unmet sexual health-care needs. Management strategies predominately involve pharmacological interventions to address the direct physiological effects of prostate cancer treatment on erectile function. However, the aetiology of sexual dysfunction is multifaceted and considerable physiological and psychological adverse effects of prostate cancer treatments, which are not addressed by pharmacological intervention, contribute to sexual dysfunction. Exercise has established efficacy for improving many of these factors in men with prostate cancer, including changes in body composition (especially to counteract body feminization), fatigue, physical function, risk of comorbid conditions, depression, anxiety and quality of life. Emerging evidence indicates that exercise also has a positive effect on sexual desire and sexual activity in men with prostate cancer.
    Nature Reviews Urology 10/2013; · 4.79 Impact Factor
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    ABSTRACT: Aging skeletal muscle is associated with not only a reduction in muscle size and strength but also in muscle quality which reflects an increase in fatty infiltration of muscle. In men with prostate cancer, androgen deprivation therapy (ADT) accelerates this loss of muscle size and strength, but it is unknown if muscle quality is also adversely affected. Therefore, we examined the effects of ADT on muscle attenuation, an indirect measure of intramuscular lipid content, as well as the muscle cross-sectional area (CSA) in men with prostate cancer. Pre- and post-CT scans of the pelvis in 39 men aged 49-78 years receiving leuprorelin were examined. The time between baseline and follow-up scans was 14.6-20 weeks after the commencement of ADT. Changes in skeletal muscle attenuation in Hounsfield units of the rectus femoris and the CSA of the rectus femoris, sartorius and quadricep muscles were assessed. Muscle attenuation of the rectus femoris muscle was significantly reduced following the initiation of ADT by 18.9% (P < 0.001). In addition, there was a significant decrease (P < 0.001) in the CSA for the sartorius, quadriceps and rectus femoris muscles. There was no effect of Zometa on muscle attenuation or muscle CSA. Our results indicate that not only muscle size but also muscle quality may be adversely affected by the undertaking of ADT in men with prostate cancer. Consequently, interventions to counteract deteriorations to both muscle mass and possibly muscle quality should be considered in men receiving ADT.
    Journal of Medical Imaging and Radiation Oncology 10/2013; · 0.98 Impact Factor
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    ABSTRACT: The objective of the current study was to identify mediators of the effects of a combined resistance and aerobic exercise program on perceived physical and general health in men undergoing androgen deprivation therapy for prostate cancer. In total, 57 patients with prostate cancer undergoing androgen deprivation therapy were randomly assigned to 12 weeks of resistance and aerobic exercise or usual care. The outcome measures of physical and general health were assessed by standardized questionnaires. Linear regression analyses were conducted on the residual change scores of the variables. The mediating effects of fatigue, muscle strength, and functional performance on the intervention's effect on physical and general health were examined using the product of coefficients method. Bootstrapping was used to calculate the 95% confidence intervals (95% CIs). The exercise intervention was found to significantly improve physical (beta, 5.03; 95% CI, 1.01-9.04) and general health (beta, 12.89; 95% CI, 2.24-23.54). Upper body muscle strength and walking speed significantly mediated the intervention effect on physical health (beta, 2.65; 95% CI, 0.64-5.54), accounting for 53% of the total effect. Walking speed and fatigue were found to be mediators in the intervention effect on general health (beta, 7.52; 95% CI, 2.16-16.92), accounting for 51% of the total effect. The intervention effects on physical and general health were explained by different mediating mechanisms. Walking speed mediated the intervention effect on both physical and general health. The intervention effect on physical health was further mediated by upper body strength, whereas the effect on general health was mediated by fatigue. Cancer 2013. © 2013 American Cancer Society.
    Cancer 10/2013; · 5.20 Impact Factor
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    ABSTRACT: Long-term prostate cancer (PCa) survivors are at increased risk for comorbidities and physical deconditioning. To determine the effectiveness of a year-long randomised controlled trial of exercise training in PCa survivors >5 yr postdiagnosis on physical functioning. Between 2010 and 2011, 100 long-term PCa survivors from Trans-Tasman Radiation Oncology Group 03.04 Randomised Androgen Deprivation and Radiotherapy previously treated with androgen-deprivation therapy and radiation therapy were randomly assigned to 6 mo of supervised exercise followed by 6 mo of a home-based maintenance programme (n=50) or printed educational material about physical activity (n=50) for 12 mo across 13 university-affiliated exercise clinics in Australia and New Zealand. Supervised resistance and aerobic exercise or printed educational material about physical activity. The primary end point was a 400-m walk as a measure of cardiovascular fitness. Secondary end points were physical function, patient-reported outcomes, muscle strength, body composition, and biomarkers. Analysis of covariance was used to compare outcomes for groups at 6 and 12 mo adjusted for baseline values. Participants undergoing supervised exercise showed improvement in cardiorespiratory fitness performance at 6 mo (-19 s [p=0.029]) and 12 mo (-13 s [p=0.028]) and better lower-body physical function across the 12-mo period (p<0.01). Supervised exercise also improved self-reported physical functioning at 6 (p=.006) and 12 mo (p=0.002), appendicular skeletal muscle at 6 mo (p=0.019), and objective measures of muscle strength at 6 and 12 mo (p<0.050). Limitations included the restricted number of participants undertaking body composition assessment, no blinding to group assignment for physical functioning measures, and inclusion of well-functioning individuals. Supervised exercise training in long-term PCa survivors is more effective than physical activity educational material for increasing cardiorespiratory fitness, physical function, muscle strength, and self-reported physical functioning at 6 mo. Importantly, these benefits were maintained in the long term with a home-based programme with follow-up at 12 mo. The effect of an exercise intervention on cardiovascular and metabolic risk factors in prostate cancer patients from the RADAR study, ACTRN: ACTRN12609000729224.
    European Urology 10/2013; · 10.48 Impact Factor
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    ABSTRACT: The purpose of the present study was to examine a possible dose-response between pre-exercise pseudoephedrine intake and cycling time trial performance. Ten trained male endurance cyclists (26.5±6.2 years, 75.1±5.9kg, 70.6±6.8mLkg(-1)min(-1)) undertook three cycling time trials in which a fixed amount of work (7kJkg(-1) body mass) was completed in the shortest possible time. Sixty minutes before the start of exercise, subjects orally ingested either 2.3mgkg(-1) or 2.8mgkg(-1) body mass of pseudoephedrine or a placebo in a randomised and double-blind manner. Venous blood was sampled at baseline, pre- and post-warm up and post-exercise for the analysis of pH and lactate and glucose concentrations; plasma catecholamine and pseudoephedrine concentrations were measured at all times except post-warm up. Cycling time trial performance (∼30min) was not enhanced by pseudoephedrine ingestion. Plasma pseudoephedrine concentration increased from pre-warm up to post-exercise in both treatment conditions, with the 2.8mgkg(-1) body mass dose producing the highest concentration at both time points (2.8mgkg(-1)>2.3mgkg(-1)>placebo; p<0.001). There was large individual variation in plasma pseudoephedrine concentration between subjects following pseudoephedrine administration. A number of factors clearly influence the uptake and appearance of pseudoephedrine in the blood and these are not yet fully understood. Combined with subsequent differences in plasma pseudoephedrine between individuals, this may partially explain the present findings and also the inconsistencies in performance following pseudoephedrine administration in previous studies.
    Journal of science and medicine in sport / Sports Medicine Australia. 08/2013;
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    ABSTRACT: Background:Due to concerns of fragility fracture, exercise is a perceived contraindication for prostate cancer patients with bone metastases. These patients experience significant functional impairment and muscle atrophy, which may lead to an increased likelihood of skeletal complications (i.e., pathological fracture, bone pain) and/or falls. Safe resistance exercise prescription may counteract this effect. The aim of this feasibility trial was to determine the safety and efficacy of resistance exercise by prostate cancer survivors with bone metastatic disease.Methods:Twenty men with established bone metastases secondary to prostate cancer were randomly assigned to a 12-week resistance exercise program in which exercise prescription was based on the location of bone lesions (n=10) or usual care (n=10). Outcomes included safety and tolerance of the exercise program, physical function, physical activity level, body composition, fatigue, quality of life and psychological distress. Outcomes were compared between groups using analysis of covariance adjusted for baseline values.Results:Participants had significant disease load with 65% of participants presenting with two or more regions affected by bone metastases and an average Gleason score of 8.2±0.9. Five participants (exercise=2; usual care=3) did not complete the intervention, three of which were due to advancing disease (exercise=2; usual care=1). No adverse events or skeletal complications occurred during the supervised exercise sessions. The exercise program was well tolerated as evidenced by high attendance (83%) and compliance rates (93%), and the ability of the participants to exercise at an intensity within the target range for cancer survivors (rating of perceived exertion =13.8±1.5). The change in physical function (muscle strength ∼11%; submaximal aerobic exercise capacity ∼5% and ambulation ∼12%), physical activity level (∼24%) and lean mass (∼3%) differed significantly between groups following the intervention, with favorable changes in the exercise group compared with the usual care group. No significant between-group differences were observed for fatigue, quality of life or psychological distress.Conclusions:This initial evidence involving a small sample size suggests that appropriately designed and supervised resistance exercise may be safe and well tolerated by prostate cancer patients with bone metastatic disease and can lead to improvements in physical function, physical activity levels and lean mass. Future trials involving larger sample sizes are required to expand these preliminary findings.Prostate Cancer and Prostatic Disease advance online publication, 6 August 2013; doi:10.1038/pcan.2013.22.
    Prostate cancer and prostatic diseases 08/2013; · 2.10 Impact Factor
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    ABSTRACT: To determine whether differences in training status, body composition and/or habitual caffeine intake influenced serum caffeine concentrations following caffeine ingestion. Single-blind. Trained cyclists/triathletes (n=14) and active (n=14) males consumed 6mgkg(-1) anhydrous caffeine. Peak, total and time to peak serum caffeine concentrations were determined from venous blood samples at baseline and 6 time-points over 4h following intake. Body composition was assessed by dual energy X-ray absorptiometry and habitual caffeine intake by a questionnaire. Trained cyclists/triathletes had 16% lower peak caffeine concentrations following caffeine ingestion compared to active individuals, although this was not statistically significant (p=0.066). There was no significant difference between trained cyclists/triathletes and active males in total (p=0.131) or time to peak (p=0.249) serum caffeine concentrations. Fat mass was significantly associated with total (r=0.427, p=0.038) but not peak (r=0.343, p=0.101) or time to peak serum caffeine concentration (β=0.00008, p=0.961). There were no associations between habitual caffeine intake and peak, total or time to peak serum caffeine concentrations. Following caffeine ingestion three findings from the study were evident: (1) endurance-trained athletes trended towards lower peak caffeine concentrations compared to active males; (2) higher fat mass was associated with higher concentrations of caffeine in the blood over 4h, and (3) habitual caffeine intake does not appear to influence serum caffeine concentrations. Identification of the optimal conditions to ensure peak availability of caffeine within the blood and/or overcoming some of the variation in how individuals respond to caffeine requires consideration of the training status and body composition of the athlete.
    Journal of science and medicine in sport / Sports Medicine Australia. 08/2013;
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    ABSTRACT: Although trials have shown that exercise has positive effects on bone mineral density (BMD), the majority of exercise trials have been conducted in older women. The aim of this study was to systematically review trials examining the effect of weight-bearing and resistance-based exercise modalities on the BMD of hip and lumbar spine of middle-aged and older men. Eight electronic databases were searched in August 2012. Randomised controlled or controlled trials that assessed the effect of weight-bearing and resistance-based exercise interventions on BMD measured by dual-energy x-ray absorptiometry, and reported effects in middle-aged and older men were included. Eight trials detailed in nine papers were included. The interventions included walking (n = 2), resistance training (n = 3), walking + resistance training (n = 1), resistance training + impact-loading activities (n = 1) and resistance training + Tai Chi (n = 1). Five of the eight trials achieved a score of less than 50 % on the modified Delphi quality rating scale. Further, there was heterogeneity in the type, intensity, frequency and duration of the exercise regimens. Effects of exercise varied greatly among studies, with six interventions having a positive effect on BMD and two interventions having no significant effect. It appears that resistance training alone or in combination with impact-loading activities are most osteogenic for this population, whereas the walking trials had limited effect on BMD. Therefore, regular resistance training and impact-loading activities should be considered as a strategy to prevent osteoporosis in middle-aged and older men. High quality randomised controlled trials are needed to establish the optimal exercise prescription.
    Osteoporosis International 04/2013; · 4.04 Impact Factor
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    ABSTRACT: Background:Previous research has shown exercise to be an effective method to mitigate many adverse treatment-related effects of androgen suppression therapy (AST) but the potential impact of exercise on sexual activity remains unknown. The purpose of this investigation was to report the effect of a 12-week exercise program on sexual activity in prostate cancer patients undergoing AST.Methods:Fifty-seven prostate cancer patients undergoing AST were randomly assigned to an exercise program (resistance and aerobic modes; n=29) or usual care control (n=28). Sexual activity was assessed by the European Organization for Research and Treatment of Cancer prostate cancer-specific quality of life questionnaire (QLQ-PR25).Results:QLQ-PR25 data were log transformed and analysis of covariance was used to compare sexual activity between groups following the intervention adjusted for baseline activity. No differences in sexual activity were observed between the exercise and control groups before the intervention. There was a significant (P=0.045) adjusted group difference in sexual activity following the 12-week intervention. Patients undergoing usual care decreased sexual activity while patients in the exercise program maintained their level of sexual activity. At baseline, 20.6 and 22.2% of participants in the exercise and control groups reported a major interest in sex (that is, high libido). Following the intervention, the exercise group had a significantly higher percentage of participants reporting a major interest in sex (exercise=17.2% vs control=0%; P=0.024).Conclusions:Participation in a short-term exercise program resulted in the maintenance of sexual activity in prostate cancer patients undergoing AST.Prostate Cancer and Prostatic Disease advance online publication, 15 January 2013; doi:10.1038/pcan.2012.52.
    Prostate cancer and prostatic diseases 01/2013; · 2.10 Impact Factor
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    ABSTRACT: Protein glycosylation via O-linked N-acetylglucosaminylation (O-GlcNAcylation) is an important post-translational regulatory mechanism mediated by O-GlcNAc transferase (OGT) and responsive to nutrients and stress. OGT attaches an O-GlcNAc moiety to proteins, while O-GlcNAcase (OGA) catalyzes O-GlcNAc removal. In skeletal muscle of experimental animals, prolonged increase in O-GlcNAcylation associates with age and muscle atrophy. Here we examined the effects of hormone replacement therapy (HRT) and power training (PT) on muscle OGT and OGA gene expression in postmenopausal women generally prone to age-related muscle weakness. In addition, the associations of OGT and OGA gene expressions with muscle phenotype were analyzed. Twenty-seven 50–57-year-old women participated in a yearlong randomized placebo-controlled trial: HRT (n = 10), PT (n = 8) and control (n = 9). OGT and OGA mRNA levels were measured from muscle samples obtained at baseline and after one year. Knee extensor muscle cross-sectional area (CSA), knee extension force, running speed and vertical jumping height were measured. During the yearlong intervention, HRT suppressed the aging-associated upregulation of OGT mRNA that occurred in the controls. The effects of PT were similar but weaker. HRT also tended to increase the OGA mRNA level compared to the controls. The change in the ratio of OGT to OGA gene expressions correlated negatively with the change in muscle CSA. Our results suggest that OGT and OGA gene expressions are associated with muscle size during the critical postmenopausal period. HRT and PT influence muscle OGT and OGA gene expression, which may be one of the mechanisms by which HRT and PT prevent aging-related loss of muscle mass.
    Experimental gerontology 01/2013; 48(12):1501–1504. · 3.34 Impact Factor
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    ABSTRACT: PURPOSE: This study examined the influence of pre-exercise food intake on plasma PSE concentrations and subsequent high intensity exercise. Additionally, urinary PSE concentrations were measured under the same conditions and compared to the present WADA threshold. METHODS: Ten highly trained male cyclists and triathletes (age 30.6 ± 6.6 years, body mass 72.9 ± 5.1 kg, O2max 64.8 ± 4.5 ml·kgmin) undertook four cycling time trials (TTs) each requiring the completion of a set amount of work (7 kJ·kg BM) in the shortest possible time. Participants were randomized into a fed or non-fed condition and orally ingested 2.8 mg·kg BM of PSE or a placebo (PLA) 90 min before exercise; in the fed trials, they consumed a meal providing 1.5 g·kg BM of carbohydrate. Venous blood was sampled at 30, 50, 70 min and pre-warm up and post-exercise for the analysis of plasma PSE and catecholamine concentrations, urine was also collected for the analysis of PSE concentration. RESULTS: Independent of the pre-exercise meal, 2.8 mg·kg BM of PSE did not significantly improve cycling TT performance. The fed trials resulted in lower plasma PSE concentrations at all time points compared to the non-fed trials. Both plasma epinephrine and blood lactate concentrations were higher in the PSE compared to the placebo trials and pre- and post-exercise urinary PSE concentrations were significantly higher than the threshold (150 μg·mL) used by WADA to determine illicit PSE use. CONCLUSIONS: Irrespective of the pre-exercise meal, cycling TT performance of ~30 min was not improved following PSE supplementation. Furthermore, 2.8 mg·kg BM of PSE taken 90 min before exercise, with or without food, resulted in urinary PSE concentrations exceeding the present WADA threshold.
    Medicine and science in sports and exercise 12/2012; · 4.48 Impact Factor
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    ABSTRACT: BACKGROUND: There has been substantial increase in use of androgen deprivation therapy as adjuvant management of prostate cancer. However, this leads to a range of musculoskeletal toxicities including reduced bone mass and increased skeletal fractures compounded with rapid metabolic alterations, including increased body fat, reduced lean mass, insulin resistance and negative lipoprotein profile, increased incidence of cardiovascular and metabolic morbidity, greater distress and reduced quality of life. Numerous research studies have demonstrated certain exercise prescriptions to be effective at preventing or even reversing these treatment toxicities. However, all interventions to date have been of rehabilitative intent being implemented after a minimum of 3 months since initiation of androgen deprivation, by which time considerable physical and psychological health problems have manifested. The pressing question is whether it is more efficacious to commence exercise therapy at the same time as initiating androgen deprivation, so treatment induced adverse effects can be immediately attenuated or indeed prevented.Methods/designWe are proposing a multi-site randomized controlled trial with partial crossover to examine the effects of timing of exercise implementation (immediate or delayed) on preserving long-term skeletal health, reversing short- and long-term metabolic and cardiovascular risk factors, and supporting mental health in men receiving androgen deprivation therapy. 124 men who are about to initiate androgen deprivation for prostate cancer will be randomized to immediate or delayed groups. Immediate will commence a 6-month exercise program within 7--10 days of their first dose. Delayed will receive usual care for 6 months and then commence the exercise program for 6 months (partial cross-over). Immediate will be free to adopt the lifestyle of their choosing following the initial 6-month intervention. Measurements for primary and secondary endpoints will take place at baseline, 6 months and 12 months. DISCUSSION: This project is unique as it explores a fundamental question of when exercise implementation will be of most benefit and addresses both physical and psychological consequences of androgen deprivation initiation. The final outcome may be adjunct treatment which will reduce if not prevent the toxicities of androgen deprivation, ultimately resulting in reduced morbidity and mortality for men with prostate cancer.Trial registrationACTRN12612000097842.
    BMC Cancer 09/2012; 12(1):432. · 3.33 Impact Factor
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    ABSTRACT: OBJECTIVES: To examine the effect of a high carbohydrate meal on serum caffeine concentration following caffeine intake. DESIGN: Randomised, double-blind, crossover. METHODS: Fourteen healthy males randomly completed 4 trials, each separated by 5 days. Participants either remained fasted (on 2 occasions) or ingested a high carbohydrate meal (2.0gkg(-1) carbohydrate, 42.4±0.6kJkg(-1)) prior to consuming either 6 or 9mgkg(-1) anhydrous caffeine. Venous blood was sampled for the analysis of serum caffeine at baseline and at 6 time-points over 4h following caffeine intake. RESULTS: Peak caffeine concentration occurred 60min following ingestion for both the 6 and 9mgkg(-1) fasted (p<0.001) trials compared to 120 and 180min following ingestion for the 6 and 9mgkg(-1) fed trials, respectively (p<0.001). Peak concentration was greater in the 9mgkg(-1) fasted trial than the corresponding fed condition (70±9μmolL(-1) and 56±6μmolL(-1), respectively) and both were greater than the 6mgkg(-1) conditions (44±8μmolL(-1) and 38±8μmolL(-1) for 6mgkg(-1) fasted and fed, respectively). Area under the caffeine curve was significantly greater (p<0.001) in the 9mgkg(-1) fasted trial (3262μmolL(-1)h(-1)), whilst areas were lowest in the 6mgkg(-1) fed trial (1644μmolL(-1)h(-1)). CONCLUSIONS: A high carbohydrate meal consumed prior to caffeine ingestion significantly reduced serum caffeine concentrations and delayed time to peak concentration. Differences in research findings between caffeine supplementation studies may, at least in part, be related to variations in postprandial timing of caffeine intake. The influence of postprandial timing should be considered when athletes consume caffeine with the aim of enhancing performance.
    Journal of science and medicine in sport / Sports Medicine Australia. 09/2012;

Publication Stats

4k Citations
403.70 Total Impact Points

Institutions

  • 2005–2014
    • Edith Cowan University
      • School of Exercise and Health Sciences
      Joondalup, Western Australia, Australia
  • 2013
    • Institute for Health and Care Research
      Amsterdamo, North Holland, Netherlands
  • 2011–2013
    • University of Newcastle
      • School of Environmental and Life Sciences
      Newcastle, New South Wales, Australia
  • 2004–2013
    • University of Queensland 
      • School of Human Movement Studies
      Brisbane, Queensland, Australia
  • 2003–2009
    • University of California, San Francisco
      • Department of Radiology and Biomedical Imaging
      San Francisco, CA, United States
  • 2007
    • Wake Forest School of Medicine
      • Sticht Center on Aging
      Winston-Salem, NC, United States
  • 2001–2004
    • University of Jyväskylä
      • Department of Health Sciences
      Jyväskylä, Western Finland, Finland
  • 2000–2004
    • National Institute on Aging
      • Laboratory of Epidemiology, Demography and Biometry (LEDB)
      Baltimore, MD, United States
  • 2002
    • VU University Medical Center
      • Department of Psychiatry
      Amsterdamo, North Holland, Netherlands
  • 2000–2001
    • National Institutes of Health
      • Laboratory of Epidemiology, Demography, and Biometry (LEDB)
      Bethesda, MD, United States
  • 1995–2000
    • Stanford University
      • Department of Medicine
      Palo Alto, California, United States
    • Palo Alto Research Center
      Palo Alto, California, United States
    • Oregon State University
      • Bone Research Laboratory
      Corvallis, OR, United States
  • 1999
    • University of Southern California
      • Department of Exercise Science
      Los Angeles, CA, United States
  • 1997–1999
    • Minneapolis Veterans Affairs Hospital
      Minneapolis, Minnesota, United States