The influence of glycerol hyperhydration on run performance within an Olympic distance triathlon
- Authors: Van Ewyk, Gerald
- Date: 2004
- Type: Text , Thesis , Masters
- Full Text:
- Description: This study was designed to determine the impact of glycerol hyperhydration, compared with a placebo hyperhydration, on the run performance during an Olympic distance triathlon. Ten competitive triathletes (mean peak oxygen consumption, VO2 peak = 65.5 ± 5.5 ml.kg.-1min-1) undertook two simulated Olympic Distance Triathlons in 31° C and 61% relative humidity. The trials were split into two work phases: a fixed workload phase comprising a 18-20 min swim and a 60 min cycle and, a self regulated time trial run over 10 kilometres conducted on a treadmill. One hundred and fifty min prior each trial, either a glycerol solution (1 g.kg.-1 body mass (BM) in a 4% carbohydrate – electrolyte drink) or a placebo of equal volume of the 4% carbohydrate-electrolyte solution was ingested over one hour. The total fluid intake in each trial was 23 ml.kg.-1 BM. A randomised, double blind, cross over design was used. Due to either 1) the arduous nature of the trials 2) the side effects associated with the ingestion of glycerol 3) or the combination of the two aforementioned reasons, only five of the 10 subjects completed the final 10 km self regulated time trial for both treatments. Only the data obtained from these five subjects were reported in this study. Glycerol ingestion expanded body water over the placebo by 154 ml (26%). At 60 and 90 min after the start of drinking, urine output was significantly higher with glycerol than placebo treatment (216.4, 366.4 ml vs 81.0, 242.0 ml, respectively) but significantly higher at 120 min in the placebo (421.6 ml vs 131.2 ml). There were no significant differences in heart rate and rectal temperature during the swim and cycle phases. However, there were significant increases in heart rate (at 5, 10, 15, 25 and 30 min) and rectal temperature (at 5, 20 and 30 min) during the 10 km run in the glycerol trial. The mean 10 km run time for the placebo trial was 40 min 21 sec (± 2.9 min) while the glycerol trial was 39 min 22 sec (± 2.0 min). The mean difference of 2.1% in finishing time between trials was not significant. Three of the five subjects in the glycerol trial improved their 10 km time by 7.0, 2.4 and 2.7%, respectively. The finishing time for one subject did not change for both trials while another subject had deteriorated by 2.3% in the glycerol trial. In the glycerol treatment, five subjects complained of bloating and nausea while only one subject complained of feeling unwell in the placebo treatment. Data from this study have shown that glycerol hyperhydration did not significantly improve performance while plasma volume expansion and subsequent lower rectal temperature and lower heart rates were not evident. The exact mechanisms of how glycerol hyperhydration can improve performance warrant further investigation.
- Description: Masters in Applied Science
- Authors: Van Ewyk, Gerald
- Date: 2004
- Type: Text , Thesis , Masters
- Full Text:
- Description: This study was designed to determine the impact of glycerol hyperhydration, compared with a placebo hyperhydration, on the run performance during an Olympic distance triathlon. Ten competitive triathletes (mean peak oxygen consumption, VO2 peak = 65.5 ± 5.5 ml.kg.-1min-1) undertook two simulated Olympic Distance Triathlons in 31° C and 61% relative humidity. The trials were split into two work phases: a fixed workload phase comprising a 18-20 min swim and a 60 min cycle and, a self regulated time trial run over 10 kilometres conducted on a treadmill. One hundred and fifty min prior each trial, either a glycerol solution (1 g.kg.-1 body mass (BM) in a 4% carbohydrate – electrolyte drink) or a placebo of equal volume of the 4% carbohydrate-electrolyte solution was ingested over one hour. The total fluid intake in each trial was 23 ml.kg.-1 BM. A randomised, double blind, cross over design was used. Due to either 1) the arduous nature of the trials 2) the side effects associated with the ingestion of glycerol 3) or the combination of the two aforementioned reasons, only five of the 10 subjects completed the final 10 km self regulated time trial for both treatments. Only the data obtained from these five subjects were reported in this study. Glycerol ingestion expanded body water over the placebo by 154 ml (26%). At 60 and 90 min after the start of drinking, urine output was significantly higher with glycerol than placebo treatment (216.4, 366.4 ml vs 81.0, 242.0 ml, respectively) but significantly higher at 120 min in the placebo (421.6 ml vs 131.2 ml). There were no significant differences in heart rate and rectal temperature during the swim and cycle phases. However, there were significant increases in heart rate (at 5, 10, 15, 25 and 30 min) and rectal temperature (at 5, 20 and 30 min) during the 10 km run in the glycerol trial. The mean 10 km run time for the placebo trial was 40 min 21 sec (± 2.9 min) while the glycerol trial was 39 min 22 sec (± 2.0 min). The mean difference of 2.1% in finishing time between trials was not significant. Three of the five subjects in the glycerol trial improved their 10 km time by 7.0, 2.4 and 2.7%, respectively. The finishing time for one subject did not change for both trials while another subject had deteriorated by 2.3% in the glycerol trial. In the glycerol treatment, five subjects complained of bloating and nausea while only one subject complained of feeling unwell in the placebo treatment. Data from this study have shown that glycerol hyperhydration did not significantly improve performance while plasma volume expansion and subsequent lower rectal temperature and lower heart rates were not evident. The exact mechanisms of how glycerol hyperhydration can improve performance warrant further investigation.
- Description: Masters in Applied Science
Cardiac response to exercise in normal ageing : What can we learn from masters athletes?
- Beaumont, Alexander, Campbell, Amy, Grace, Fergal, Sculthorpe, Nicholas
- Authors: Beaumont, Alexander , Campbell, Amy , Grace, Fergal , Sculthorpe, Nicholas
- Date: 2018
- Type: Text , Journal article , Review
- Relation: Current Cardiology Reviews Vol. 14, no. 4 (2018), p. 245-253
- Full Text:
- Reviewed:
- Description: Background: Ageing is associated with an inexorable decline in cardiac and vascular function, resulting in an increased risk of Cardiovascular Disease (CVD). Lifestyle factors such as exercise have emerged as a primary therapeutic target in the prevention of CVD, yet older individuals are frequently reported as being the least active, with few meeting the recommended physical activity guidelines. In contrast, well trained older individuals (Masters athletes) have superior functional capacity than their sedentary peers and are often comparable with young non-athletes. Therefore, the 'masters' athlete may be viewed as a unique non-pharmacological model which may allow researchers to disentangle the inexorable from the preventable and the magnitude of the unavoidable 'true' reduction in cardiac function due to ageing. Conclusion: This review examines evidence from studies which have compared cardiac structure and function in well trained older athletes, with age-matched controls but otherwise healthy. © 2018 Bentham Science Publishers.
- Authors: Beaumont, Alexander , Campbell, Amy , Grace, Fergal , Sculthorpe, Nicholas
- Date: 2018
- Type: Text , Journal article , Review
- Relation: Current Cardiology Reviews Vol. 14, no. 4 (2018), p. 245-253
- Full Text:
- Reviewed:
- Description: Background: Ageing is associated with an inexorable decline in cardiac and vascular function, resulting in an increased risk of Cardiovascular Disease (CVD). Lifestyle factors such as exercise have emerged as a primary therapeutic target in the prevention of CVD, yet older individuals are frequently reported as being the least active, with few meeting the recommended physical activity guidelines. In contrast, well trained older individuals (Masters athletes) have superior functional capacity than their sedentary peers and are often comparable with young non-athletes. Therefore, the 'masters' athlete may be viewed as a unique non-pharmacological model which may allow researchers to disentangle the inexorable from the preventable and the magnitude of the unavoidable 'true' reduction in cardiac function due to ageing. Conclusion: This review examines evidence from studies which have compared cardiac structure and function in well trained older athletes, with age-matched controls but otherwise healthy. © 2018 Bentham Science Publishers.
A prospective cohort study on symptoms of common mental disorders among Dutch elite athletes
- Gouttebarge, Vincent, Jonkers, Ruud, Moen, Maarten, Verhagen, Evert, Wylleman, Paul, Kerkhoffs, Gino
- Authors: Gouttebarge, Vincent , Jonkers, Ruud , Moen, Maarten , Verhagen, Evert , Wylleman, Paul , Kerkhoffs, Gino
- Date: 2017
- Type: Text , Journal article
- Relation: Physician and Sportsmedicine Vol. 45, no. 4 (2017), p. 426-432
- Full Text:
- Reviewed:
- Description: Objective: Scientific knowledge about symptoms of common mental disorders in elite sports is scarce. Consequently, the objectives of the study were to (i) establish the 12-month incidence of symptoms of common mental disorders (CMD; distress, anxiety/depression, sleep disturbance, adverse alcohol use, eating disorders) among Dutch elite athletes and (ii) explore their potential association with several stressors (being injured, recent life events, career dissatisfaction).Methods: A prospective cohort study with a 12-month follow-up period was conducted. The study used validated questionnaires to assess symptoms of common mental disorders (thus not clinically diagnosed) as well as several stressors; an electronic questionnaire was set up and repeatedly distributed.Results: A total of 203 elite athletes gave their written informed consent to participate in the study, from which 143 completed the 12-month follow-up period (follow-up rate of 70%). Incidence of symptoms of CMD ranged from 6% for adverse alcohol use to 57% for symptoms of anxiety/depression. Over the follow-up period, around 17% of the participants reported two simultaneous symptoms of CMD, and around 19% reported three simultaneous symptoms of CMD. Inferences between some stressors and symptoms of CMD were found but none of the associations were statistically significant.Conclusions: Substantial 12-month incidence rates of symptoms of CMD (self-reported and not clinically diagnosed) were found among Dutch elite athletes (especially for anxiety/depression), appearing similar to the ones found among athletes from other sports disciplines and the Dutch general population. Also, inferences between some stressors and symptoms of CMD were found but none of the associations were statistically significant. Supportive and preventive measures directed towards symptoms of CMD should be developed to improve awareness and psychological resilience of athletes, which would likely improve their performance and quality-of-life.
- Authors: Gouttebarge, Vincent , Jonkers, Ruud , Moen, Maarten , Verhagen, Evert , Wylleman, Paul , Kerkhoffs, Gino
- Date: 2017
- Type: Text , Journal article
- Relation: Physician and Sportsmedicine Vol. 45, no. 4 (2017), p. 426-432
- Full Text:
- Reviewed:
- Description: Objective: Scientific knowledge about symptoms of common mental disorders in elite sports is scarce. Consequently, the objectives of the study were to (i) establish the 12-month incidence of symptoms of common mental disorders (CMD; distress, anxiety/depression, sleep disturbance, adverse alcohol use, eating disorders) among Dutch elite athletes and (ii) explore their potential association with several stressors (being injured, recent life events, career dissatisfaction).Methods: A prospective cohort study with a 12-month follow-up period was conducted. The study used validated questionnaires to assess symptoms of common mental disorders (thus not clinically diagnosed) as well as several stressors; an electronic questionnaire was set up and repeatedly distributed.Results: A total of 203 elite athletes gave their written informed consent to participate in the study, from which 143 completed the 12-month follow-up period (follow-up rate of 70%). Incidence of symptoms of CMD ranged from 6% for adverse alcohol use to 57% for symptoms of anxiety/depression. Over the follow-up period, around 17% of the participants reported two simultaneous symptoms of CMD, and around 19% reported three simultaneous symptoms of CMD. Inferences between some stressors and symptoms of CMD were found but none of the associations were statistically significant.Conclusions: Substantial 12-month incidence rates of symptoms of CMD (self-reported and not clinically diagnosed) were found among Dutch elite athletes (especially for anxiety/depression), appearing similar to the ones found among athletes from other sports disciplines and the Dutch general population. Also, inferences between some stressors and symptoms of CMD were found but none of the associations were statistically significant. Supportive and preventive measures directed towards symptoms of CMD should be developed to improve awareness and psychological resilience of athletes, which would likely improve their performance and quality-of-life.
Aerobic training protects cardiac function during advancing age : A meta-analysis of four decades of controlled studies
- Beaumont, Alexander, Grace, Fergal, Richards, Joanna, Campbell, Amy, Sculthorpe, Nicholas
- Authors: Beaumont, Alexander , Grace, Fergal , Richards, Joanna , Campbell, Amy , Sculthorpe, Nicholas
- Date: 2019
- Type: Text , Journal article , Review
- Relation: Sports Medicine Vol. 49, no. 2 (2019), p. 199-219
- Full Text:
- Reviewed:
- Description: Background: In contrast to younger athletes, there is comparatively less literature examining cardiac structure and function in older athletes. However, a progressive accumulation of studies during the past four decades offers a body of literature worthy of systematic scrutiny. Objectives: We conducted a systematic review, meta-analysis and meta-regression of controlled echocardiography studies comparing left ventricular (LV) structure and function in aerobically trained older athletes (> 45 years) with age-matched untrained controls, in addition to investigating the influence of chronological age. Methods: Electronic databases were searched from inception to January 2018 before conducting a random-effects meta-analysis to calculate pooled differences in means, effect size and 95% confidence intervals (CIs). Study heterogeneity was reported using Cochran’s Q and I2 statistic. Results: Overall, 32 studies (644 athletes; 582 controls) were included. Athletes had greater LV end-diastolic diameter (3.65 mm, 95% CI 2.66–4.64), interventricular septal thickness (1.23 mm, 95% CI 0.85–1.60), posterior wall thickness (1.20 mm, 95% CI 0.83–1.56), LV mass (72 g, 95% CI 46–98), LV mass index (28.17 g·m2, 95% CI 19.84–36.49) and stroke volume (13.59 mL, 95% CI 7.20–19.98) (all p < 0.01). Athletes had superior global diastolic function [ratio of early (E) to late (A) mitral inflow velocity (E/A) 0.18, 95% CI 0.13–0.24, p < 0.01; ratio of early (e′) to late (a′) diastolic annular tissue velocity (e′/a′) 0.23, 95% CI 0.06–0.40, p = 0.01], lower A (−8.20 cm·s−1, 95% CI −11.90 to −4.51, p < 0.01) and a′ (−0.72 cm·s−1, 95% CI −1.31 to −0.12, p = 0.02), and more rapid e′ (0.96 cm·s−1, 95% CI 0.05–1.86, p = 0.04). Meta-regression for chronological age identified that athlete–control differences, in the main, are maintained during advancing age. Conclusions: Athletic older men have larger cardiac dimensions and enjoy more favourable cardiac function than healthy, non-athletic counterparts. Notably, the athlete groups maintain these effects during chronological ageing. © 2018, The Author(s).
- Authors: Beaumont, Alexander , Grace, Fergal , Richards, Joanna , Campbell, Amy , Sculthorpe, Nicholas
- Date: 2019
- Type: Text , Journal article , Review
- Relation: Sports Medicine Vol. 49, no. 2 (2019), p. 199-219
- Full Text:
- Reviewed:
- Description: Background: In contrast to younger athletes, there is comparatively less literature examining cardiac structure and function in older athletes. However, a progressive accumulation of studies during the past four decades offers a body of literature worthy of systematic scrutiny. Objectives: We conducted a systematic review, meta-analysis and meta-regression of controlled echocardiography studies comparing left ventricular (LV) structure and function in aerobically trained older athletes (> 45 years) with age-matched untrained controls, in addition to investigating the influence of chronological age. Methods: Electronic databases were searched from inception to January 2018 before conducting a random-effects meta-analysis to calculate pooled differences in means, effect size and 95% confidence intervals (CIs). Study heterogeneity was reported using Cochran’s Q and I2 statistic. Results: Overall, 32 studies (644 athletes; 582 controls) were included. Athletes had greater LV end-diastolic diameter (3.65 mm, 95% CI 2.66–4.64), interventricular septal thickness (1.23 mm, 95% CI 0.85–1.60), posterior wall thickness (1.20 mm, 95% CI 0.83–1.56), LV mass (72 g, 95% CI 46–98), LV mass index (28.17 g·m2, 95% CI 19.84–36.49) and stroke volume (13.59 mL, 95% CI 7.20–19.98) (all p < 0.01). Athletes had superior global diastolic function [ratio of early (E) to late (A) mitral inflow velocity (E/A) 0.18, 95% CI 0.13–0.24, p < 0.01; ratio of early (e′) to late (a′) diastolic annular tissue velocity (e′/a′) 0.23, 95% CI 0.06–0.40, p = 0.01], lower A (−8.20 cm·s−1, 95% CI −11.90 to −4.51, p < 0.01) and a′ (−0.72 cm·s−1, 95% CI −1.31 to −0.12, p = 0.02), and more rapid e′ (0.96 cm·s−1, 95% CI 0.05–1.86, p = 0.04). Meta-regression for chronological age identified that athlete–control differences, in the main, are maintained during advancing age. Conclusions: Athletic older men have larger cardiac dimensions and enjoy more favourable cardiac function than healthy, non-athletic counterparts. Notably, the athlete groups maintain these effects during chronological ageing. © 2018, The Author(s).
Validating an inertial measurement unit for cricket fast bowling : a first step in assessing the feasibility of diagnosing back injury risk in cricket fast bowlers during a tele-sport-and-exercise medicine consultation
- Harnett, Keegan, Plint, Brenda, Chan, Ka, Clark, Benjamin, Netto, Kevin, Davey, Paul, Müller, Sean, Rosalie, Simon
- Authors: Harnett, Keegan , Plint, Brenda , Chan, Ka , Clark, Benjamin , Netto, Kevin , Davey, Paul , Müller, Sean , Rosalie, Simon
- Date: 2022
- Type: Text , Journal article
- Relation: PeerJ Vol. 10, no. (2022), p.
- Full Text:
- Reviewed:
- Description: This study aimed to validate an array-based inertial measurement unit to measure cricket fast bowling kinematics as a first step in assessing feasibility for tele-sport-and-exercise medicine. We concurrently captured shoulder girdle relative to the pelvis, trunk lateral flexion, and knee flexion angles at front foot contact of eight cricket medium-fast bowlers using inertial measurement unit and optical motion capture. We used one sample t-tests and 95% limits of agreement (LOA) to determine the mean difference between the two systems and Smallest Worth-while Change statistic to determine whether any differences were meaningful. A statistically significant (p < 0.001) but small mean difference of -4.7̊ ± 8.6̊ (95% Confidence Interval (CI) [-3.1̊ to -6.4̊], LOA [-22.2 to 12.7], SWC 3.9̊) in shoulder girdle relative to the pelvis angle was found between the systems. There were no statistically significant differences between the two systems in trunk lateral flexion and knee flexion with the mean differences being 0.1̊ ± 10.8̊ (95% CI [-1.9̊ to 2.2̊], LOA [-22.5 to 22.7], SWC 1.2̊) and 1.6̊ ± 10.1̊ (95% CI [-0.2̊ to 3.3̊], LOA [-19.2 to 22.3], SWC 1.9̊) respectively. The inertial measurement unit-based system tested allows for accurate measurement of specific cricket fast bowling kinematics and could be used in determining injury risk in the context of tele-sport-and-exercise-medicine. Copyright 2022 Harnett et al.
- Authors: Harnett, Keegan , Plint, Brenda , Chan, Ka , Clark, Benjamin , Netto, Kevin , Davey, Paul , Müller, Sean , Rosalie, Simon
- Date: 2022
- Type: Text , Journal article
- Relation: PeerJ Vol. 10, no. (2022), p.
- Full Text:
- Reviewed:
- Description: This study aimed to validate an array-based inertial measurement unit to measure cricket fast bowling kinematics as a first step in assessing feasibility for tele-sport-and-exercise medicine. We concurrently captured shoulder girdle relative to the pelvis, trunk lateral flexion, and knee flexion angles at front foot contact of eight cricket medium-fast bowlers using inertial measurement unit and optical motion capture. We used one sample t-tests and 95% limits of agreement (LOA) to determine the mean difference between the two systems and Smallest Worth-while Change statistic to determine whether any differences were meaningful. A statistically significant (p < 0.001) but small mean difference of -4.7̊ ± 8.6̊ (95% Confidence Interval (CI) [-3.1̊ to -6.4̊], LOA [-22.2 to 12.7], SWC 3.9̊) in shoulder girdle relative to the pelvis angle was found between the systems. There were no statistically significant differences between the two systems in trunk lateral flexion and knee flexion with the mean differences being 0.1̊ ± 10.8̊ (95% CI [-1.9̊ to 2.2̊], LOA [-22.5 to 22.7], SWC 1.2̊) and 1.6̊ ± 10.1̊ (95% CI [-0.2̊ to 3.3̊], LOA [-19.2 to 22.3], SWC 1.9̊) respectively. The inertial measurement unit-based system tested allows for accurate measurement of specific cricket fast bowling kinematics and could be used in determining injury risk in the context of tele-sport-and-exercise-medicine. Copyright 2022 Harnett et al.
Type D personality, stress, coping and performance on a novel sport task
- Borkoles, Erika, Kaiseler, Mariana, Evans, Andrew, Ski, Chantal, Thompson, David, Polman, Remco
- Authors: Borkoles, Erika , Kaiseler, Mariana , Evans, Andrew , Ski, Chantal , Thompson, David , Polman, Remco
- Date: 2018
- Type: Text , Journal article
- Relation: PLoS One Vol. 13, no. 4 (2018), p. e0196692-e0196692
- Full Text:
- Reviewed:
- Description: We investigated (1) the relationship between Type D personality, stress intensity appraisal of a self-selected stressor, coping, and perceived coping effectiveness and (2) the relationship between Type D personality and performance. In study one, 482 athletes completed the Type D personality questionnaire (DS14), stress thermometer and MCOPE in relation to a recently experienced sport stressor. Type D was associated with increased levels of perceived stress and selection of coping strategies (more emotion and avoidance coping) as well as perceptions of their effectiveness. In study two, 32 participants completed a rugby league circuit task and were assessed on pre-performance anxiety, post-performance affect and coping. Type D was associated with poorer performance (reduced distance more errors), decreases in pre-performance self-confidence and more use of maladaptive resignation/withdrawal coping. Findings suggest that Type D is associated with maladaptive coping and reduced performance. Type D individuals would benefit from interventions related to mood modification or enhancing interpersonal functioning.
- Authors: Borkoles, Erika , Kaiseler, Mariana , Evans, Andrew , Ski, Chantal , Thompson, David , Polman, Remco
- Date: 2018
- Type: Text , Journal article
- Relation: PLoS One Vol. 13, no. 4 (2018), p. e0196692-e0196692
- Full Text:
- Reviewed:
- Description: We investigated (1) the relationship between Type D personality, stress intensity appraisal of a self-selected stressor, coping, and perceived coping effectiveness and (2) the relationship between Type D personality and performance. In study one, 482 athletes completed the Type D personality questionnaire (DS14), stress thermometer and MCOPE in relation to a recently experienced sport stressor. Type D was associated with increased levels of perceived stress and selection of coping strategies (more emotion and avoidance coping) as well as perceptions of their effectiveness. In study two, 32 participants completed a rugby league circuit task and were assessed on pre-performance anxiety, post-performance affect and coping. Type D was associated with poorer performance (reduced distance more errors), decreases in pre-performance self-confidence and more use of maladaptive resignation/withdrawal coping. Findings suggest that Type D is associated with maladaptive coping and reduced performance. Type D individuals would benefit from interventions related to mood modification or enhancing interpersonal functioning.
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