Evidence of direct cardiac damage following high-intensity exercise in chronic energy restriction : A case report and literature review
- Baird, Marianne, Grace, Fergal, Sculthorpe, Nicholas, Graham, Scott, Fleming, Audrey, Baker, Julien
- Authors: Baird, Marianne , Grace, Fergal , Sculthorpe, Nicholas , Graham, Scott , Fleming, Audrey , Baker, Julien
- Date: 2017
- Type: Text , Journal article
- Relation: Medicine Vol. 96, no. 27 (2017), p. 1-7
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- Description: Rationale: Following prolonged endurance events such as marathons, elevated levels of cardiospecific biomarkers are commonly reported. Although transiently raised levels are generally not considered to indicate clinical myocardial damage, comprehension of this phenomenon remains incomplete. The popularity of high-intensity interval training highlights a paucity of research measuring cardiac biomarker response to this type of exercise. This a posteriori case report discusses the elevation of cardiac troponins (cTn) associated with short interval, high-intensity exercise. Patient concerns: In this case report, an apparently healthy 29-year-old recreationally active female presented clinically raised cardiac troponin I (cTnI) levels (>0.04 ng/mL), after performing high-intensity cycle ergometer sprints. As creatine kinase (CK) is expressed by multiple organs (e.g., skeletal muscle, brain, and myocardium), cTnI assays were performed to determine any changes in total serum CK levels not originating from skeletal muscle damage. Diagnosis: A posteriori the individual's daily energy expenditure indicated chronically low-energy availability. Psychometric testing suggested that the individual scored positive for disordered eating, highly for fatigue levels, and low in mental health components. Outcomes: The current case report provides novel evidence of elevated cTnI occurring as a result of performing short duration, high intensity, cycle ergometer exercise in an individual with self-reported chronically depleted energy balance. A schematic to identify potentially “at risk” individuals is presented. Lessons: Considering this as a case report, results cannot be generalized; however, the main findings suggest that individuals who habitually restrict their calorie intake below their bodies’ daily energy requirements, may have elevated biomarkers of exercise induced myocardial stress from performing high-intensity exercise.
- Authors: Baird, Marianne , Grace, Fergal , Sculthorpe, Nicholas , Graham, Scott , Fleming, Audrey , Baker, Julien
- Date: 2017
- Type: Text , Journal article
- Relation: Medicine Vol. 96, no. 27 (2017), p. 1-7
- Full Text:
- Reviewed:
- Description: Rationale: Following prolonged endurance events such as marathons, elevated levels of cardiospecific biomarkers are commonly reported. Although transiently raised levels are generally not considered to indicate clinical myocardial damage, comprehension of this phenomenon remains incomplete. The popularity of high-intensity interval training highlights a paucity of research measuring cardiac biomarker response to this type of exercise. This a posteriori case report discusses the elevation of cardiac troponins (cTn) associated with short interval, high-intensity exercise. Patient concerns: In this case report, an apparently healthy 29-year-old recreationally active female presented clinically raised cardiac troponin I (cTnI) levels (>0.04 ng/mL), after performing high-intensity cycle ergometer sprints. As creatine kinase (CK) is expressed by multiple organs (e.g., skeletal muscle, brain, and myocardium), cTnI assays were performed to determine any changes in total serum CK levels not originating from skeletal muscle damage. Diagnosis: A posteriori the individual's daily energy expenditure indicated chronically low-energy availability. Psychometric testing suggested that the individual scored positive for disordered eating, highly for fatigue levels, and low in mental health components. Outcomes: The current case report provides novel evidence of elevated cTnI occurring as a result of performing short duration, high intensity, cycle ergometer exercise in an individual with self-reported chronically depleted energy balance. A schematic to identify potentially “at risk” individuals is presented. Lessons: Considering this as a case report, results cannot be generalized; however, the main findings suggest that individuals who habitually restrict their calorie intake below their bodies’ daily energy requirements, may have elevated biomarkers of exercise induced myocardial stress from performing high-intensity exercise.
Sprint interval training and the school curriculum : Benefits upon cardiorespiratory fitness, physical activity profiles, and cardiometabolic risk profiles of healthy adolescents
- Martin-Smith, Rhona, Buchan, Duncan, Baker, Julien, Macdonald, Mhairi, Sculthorpe, Nicholas, Easton, Chris, Knox, Allan, Grace, Fergal
- Authors: Martin-Smith, Rhona , Buchan, Duncan , Baker, Julien , Macdonald, Mhairi , Sculthorpe, Nicholas , Easton, Chris , Knox, Allan , Grace, Fergal
- Date: 2019
- Type: Text , Journal article
- Relation: Pediatric Exercise Science Vol. 31, no. 3 (2019), p. 296-305
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- Description: Background: This study examined the impact of a 4-week school-based sprint interval training program on cardiorespiratory fitness (CRF), daily physical activity (PA) behavior, and cardiometabolic risk (CMR) outcomes in adolescents. Methods: A total of 56 adolescents (22 females) were allocated to either an intervention (n = 22; 17.0 [0.3] y) or control group (n = 30; 16.8 [0.5] y). Intervention group performed 5 to 6, 30 second "all out" running sprints, interspersed with 30-second rest intervals, 3 times per week, for 4 consecutive weeks, whereas control group performed their normal physical education lessons. CRF was estimated from the 20-m multistage fitness test and PA behavior was determined using accelerometry. Fasting blood samples were obtained to measure biochemical markers of CMR. Results: Significant group x time interactions were observed for CRF (5.03 [1.66 to 8.40]; P < .001; d = 0.95), sedentary time (136.15 [91.91 to 180.39]; P = .004; d = 1.8), moderate PA (57.20 [32.17 to 82.23]; P < .001; d = 1.5), vigorous PA (5.40 [4.22 to 6.57]; P < .001; d = 1.2), fasting insulin (0.37 [-0.48 to 1.21]; P = .01; d = 1.0), homeostasis model of assessment-insulin resistance (0.26 [0.15 to 0.42]; P < .001; d = 0.9), and clustered CMR score (0.22 [-0.05 to 0.68]; P < .001; d = 10.63). Conclusion: Findings of this study indicate that 4 weeks of school-based sprint interval training improves CRF, improves PA profiles, and maintains CMR in adolescents during the school term.
- Authors: Martin-Smith, Rhona , Buchan, Duncan , Baker, Julien , Macdonald, Mhairi , Sculthorpe, Nicholas , Easton, Chris , Knox, Allan , Grace, Fergal
- Date: 2019
- Type: Text , Journal article
- Relation: Pediatric Exercise Science Vol. 31, no. 3 (2019), p. 296-305
- Full Text:
- Reviewed:
- Description: Background: This study examined the impact of a 4-week school-based sprint interval training program on cardiorespiratory fitness (CRF), daily physical activity (PA) behavior, and cardiometabolic risk (CMR) outcomes in adolescents. Methods: A total of 56 adolescents (22 females) were allocated to either an intervention (n = 22; 17.0 [0.3] y) or control group (n = 30; 16.8 [0.5] y). Intervention group performed 5 to 6, 30 second "all out" running sprints, interspersed with 30-second rest intervals, 3 times per week, for 4 consecutive weeks, whereas control group performed their normal physical education lessons. CRF was estimated from the 20-m multistage fitness test and PA behavior was determined using accelerometry. Fasting blood samples were obtained to measure biochemical markers of CMR. Results: Significant group x time interactions were observed for CRF (5.03 [1.66 to 8.40]; P < .001; d = 0.95), sedentary time (136.15 [91.91 to 180.39]; P = .004; d = 1.8), moderate PA (57.20 [32.17 to 82.23]; P < .001; d = 1.5), vigorous PA (5.40 [4.22 to 6.57]; P < .001; d = 1.2), fasting insulin (0.37 [-0.48 to 1.21]; P = .01; d = 1.0), homeostasis model of assessment-insulin resistance (0.26 [0.15 to 0.42]; P < .001; d = 0.9), and clustered CMR score (0.22 [-0.05 to 0.68]; P < .001; d = 10.63). Conclusion: Findings of this study indicate that 4 weeks of school-based sprint interval training improves CRF, improves PA profiles, and maintains CMR in adolescents during the school term.
Six weeks of conditioning exercise increases total, but not free testosterone in lifelong sedentary aging men
- Hayes, Lawrence, Sculthorpe, Nicholas, Herbert, Peter, Baker, Julien, Spagna, Roberto, Grace, Fergal
- Authors: Hayes, Lawrence , Sculthorpe, Nicholas , Herbert, Peter , Baker, Julien , Spagna, Roberto , Grace, Fergal
- Date: 2015
- Type: Text , Journal article
- Relation: Aging Male Vol. 18, no. 3 (2015), p. 195-200
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- Description: INTRODUCTION: Advancing age is associated with a gradual decline in circulating androgens, and the putative role of exercise training on systemic androgens remains to be adequately defined. METHODS: The present investigation examined the impact of 6 weeks of supervised exercise training on resting levels of systemic hormones in a cohort of lifelong sedentary men [SED (n = 28), 62.5 +/- 5.3 years], compared with a positive control group of age-matched lifelong exercisers [LE (n = 20), 60.4 +/- 4.7 years, >30 years training history]. Blood hormones were sampled pre- and post-intervention from an antecubital forearm vein and analysed using electrochemiluminescent immunoassay. Cardiorespiratory fitness ([Formula: see text]) was determined via indirect calorimetry during an incremental cycle test to volitional exhaustion. RESULTS: Analysis of variance (ANOVA) revealed a lack of significant change in any parameter amongst LE, whilst SED experienced a significant exercise-induced improvement in cardiorespiratory fitness and total testosterone (all p < 0.05). Concurrent increases in sex hormone-binding globulin (SHBG; p < 0.05) resulted in a lack of change to either bioavailable or calculated free testosterone (p > 0.05) amongst SED. CONCLUSIONS: Although resting levels of systemic total testosterone increased in response to 6 weeks of exercise training, increases in SHBG negated any potential relationship between calculated-free or bioavailable testosterone. These findings indicate that increases in bioavailable testosterone fraction are not required for cardiorespiratory fitness improvements in aging men.
- Authors: Hayes, Lawrence , Sculthorpe, Nicholas , Herbert, Peter , Baker, Julien , Spagna, Roberto , Grace, Fergal
- Date: 2015
- Type: Text , Journal article
- Relation: Aging Male Vol. 18, no. 3 (2015), p. 195-200
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- Description: INTRODUCTION: Advancing age is associated with a gradual decline in circulating androgens, and the putative role of exercise training on systemic androgens remains to be adequately defined. METHODS: The present investigation examined the impact of 6 weeks of supervised exercise training on resting levels of systemic hormones in a cohort of lifelong sedentary men [SED (n = 28), 62.5 +/- 5.3 years], compared with a positive control group of age-matched lifelong exercisers [LE (n = 20), 60.4 +/- 4.7 years, >30 years training history]. Blood hormones were sampled pre- and post-intervention from an antecubital forearm vein and analysed using electrochemiluminescent immunoassay. Cardiorespiratory fitness ([Formula: see text]) was determined via indirect calorimetry during an incremental cycle test to volitional exhaustion. RESULTS: Analysis of variance (ANOVA) revealed a lack of significant change in any parameter amongst LE, whilst SED experienced a significant exercise-induced improvement in cardiorespiratory fitness and total testosterone (all p < 0.05). Concurrent increases in sex hormone-binding globulin (SHBG; p < 0.05) resulted in a lack of change to either bioavailable or calculated free testosterone (p > 0.05) amongst SED. CONCLUSIONS: Although resting levels of systemic total testosterone increased in response to 6 weeks of exercise training, increases in SHBG negated any potential relationship between calculated-free or bioavailable testosterone. These findings indicate that increases in bioavailable testosterone fraction are not required for cardiorespiratory fitness improvements in aging men.
The effects of a formal exercise training programme on salivary hormone concentrations and body composition in previously sedentary aging men
- Hayes, Lawrence, Grace, Fergal, Sculthorpe, Nicholas, Herbert, Peter, Ratcliffe, John, Kilduff, Liam, Baker, Julien
- Authors: Hayes, Lawrence , Grace, Fergal , Sculthorpe, Nicholas , Herbert, Peter , Ratcliffe, John , Kilduff, Liam , Baker, Julien
- Date: 2013
- Type: Text , Journal article
- Relation: SpringerPlus Vol. 2, no. 18 (2013), p. 1-5
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- Description: Alteration in body composition, physical function, and substrate metabolism occur with advancing age. These changes may be attenuated by exercise. This study examined whether twenty eight, previously sedentary males (62.5 +/- 5.3 years of age; body mass of 89.7 +/- 16.4 kg) adhering to the ACSM minimum guidelines for aerobic exercise for six weeks would improve exercise capabilities, body composition and salivary hormone profiles. After six weeks of adhering to the guidelines, salivary testosterone and vo(2max) (absolute and relative) increased (p < 0.05), whilst body fat percentage and body mass decreased (p < 0.05). Peak power output, fat free mass and cortisol values were not significantly different. Interestingly, salivary testosterone correlated inversely with body fat percentage (R(2) = .285, p = 0.011). These results suggest that despite previous inactivity, older males can achieve improvements in cardiorespiratory fitness, body composition and anabolism by adhering to simple lifestyle changes.
- Authors: Hayes, Lawrence , Grace, Fergal , Sculthorpe, Nicholas , Herbert, Peter , Ratcliffe, John , Kilduff, Liam , Baker, Julien
- Date: 2013
- Type: Text , Journal article
- Relation: SpringerPlus Vol. 2, no. 18 (2013), p. 1-5
- Full Text:
- Reviewed:
- Description: Alteration in body composition, physical function, and substrate metabolism occur with advancing age. These changes may be attenuated by exercise. This study examined whether twenty eight, previously sedentary males (62.5 +/- 5.3 years of age; body mass of 89.7 +/- 16.4 kg) adhering to the ACSM minimum guidelines for aerobic exercise for six weeks would improve exercise capabilities, body composition and salivary hormone profiles. After six weeks of adhering to the guidelines, salivary testosterone and vo(2max) (absolute and relative) increased (p < 0.05), whilst body fat percentage and body mass decreased (p < 0.05). Peak power output, fat free mass and cortisol values were not significantly different. Interestingly, salivary testosterone correlated inversely with body fat percentage (R(2) = .285, p = 0.011). These results suggest that despite previous inactivity, older males can achieve improvements in cardiorespiratory fitness, body composition and anabolism by adhering to simple lifestyle changes.
Evidence from randomised controlled trials does not support current dietary fat guidelines : A systematic review and meta-analysis
- Harcombe, Zoe, Baker, Julien, DiNicolantonio, James, Grace, Fergal, Davies, Bruce
- Authors: Harcombe, Zoe , Baker, Julien , DiNicolantonio, James , Grace, Fergal , Davies, Bruce
- Date: 2016
- Type: Text , Journal article
- Relation: Open Heart Vol. 3, no. 2 (2016), p. e000409
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- Description: OBJECTIVES: National dietary guidelines were introduced in 1977 and 1983, by the USA and UK governments, respectively, with the ambition of reducing coronary heart disease (CHD) mortality by reducing dietary fat intake. A recent systematic review and meta-analysis by the present authors, examining the randomised controlled trial (RCT) evidence available to the dietary committees during those time periods, found no support for the recommendations to restrict dietary fat. The present investigation extends our work by re-examining the totality of RCT evidence relating to the current dietary fat guidelines. METHODS: A systematic review and meta-analysis of RCTs currently available, which examined the relationship between dietary fat, serum cholesterol and the development of CHD, was undertaken. RESULTS: The systematic review included 62 421 participants in 10 dietary trials: 7 secondary prevention studies, 1 primary prevention and 2 combined. The death rates for all-cause mortality were 6.45% and 6.06% in the intervention and control groups, respectively. The risk ratio (RR) from meta-analysis was 0.991 (95% CI 0.935 to 1.051). The death rates for CHD mortality were 2.16% and 1.80% in the intervention and control groups, respectively. The RR was 0.976 (95% CI 0.878 to 1.084). Mean serum cholesterol levels decreased in all intervention groups and all but one control group. The reductions in mean serum cholesterol levels were significantly greater in the intervention groups; this did not result in significant differences in CHD or all-cause mortality. CONCLUSIONS: The current available evidence found no significant difference in all-cause mortality or CHD mortality, resulting from the dietary fat interventions. RCT evidence currently available does not support the current dietary fat guidelines. The evidence per se lacks generalisability for population-wide guidelines.
- Authors: Harcombe, Zoe , Baker, Julien , DiNicolantonio, James , Grace, Fergal , Davies, Bruce
- Date: 2016
- Type: Text , Journal article
- Relation: Open Heart Vol. 3, no. 2 (2016), p. e000409
- Full Text:
- Reviewed:
- Description: OBJECTIVES: National dietary guidelines were introduced in 1977 and 1983, by the USA and UK governments, respectively, with the ambition of reducing coronary heart disease (CHD) mortality by reducing dietary fat intake. A recent systematic review and meta-analysis by the present authors, examining the randomised controlled trial (RCT) evidence available to the dietary committees during those time periods, found no support for the recommendations to restrict dietary fat. The present investigation extends our work by re-examining the totality of RCT evidence relating to the current dietary fat guidelines. METHODS: A systematic review and meta-analysis of RCTs currently available, which examined the relationship between dietary fat, serum cholesterol and the development of CHD, was undertaken. RESULTS: The systematic review included 62 421 participants in 10 dietary trials: 7 secondary prevention studies, 1 primary prevention and 2 combined. The death rates for all-cause mortality were 6.45% and 6.06% in the intervention and control groups, respectively. The risk ratio (RR) from meta-analysis was 0.991 (95% CI 0.935 to 1.051). The death rates for CHD mortality were 2.16% and 1.80% in the intervention and control groups, respectively. The RR was 0.976 (95% CI 0.878 to 1.084). Mean serum cholesterol levels decreased in all intervention groups and all but one control group. The reductions in mean serum cholesterol levels were significantly greater in the intervention groups; this did not result in significant differences in CHD or all-cause mortality. CONCLUSIONS: The current available evidence found no significant difference in all-cause mortality or CHD mortality, resulting from the dietary fat interventions. RCT evidence currently available does not support the current dietary fat guidelines. The evidence per se lacks generalisability for population-wide guidelines.
Age related vascular endothelial function following lifelong sedentariness: positive impact of cardiovascular conditioning without further improvement following low frequency high intensity interval training
- Grace, Fergal, Herbert, Peter, Ratcliffe, John, New, Karl, Baker, Julien, Sculthorpe, Nicholas
- Authors: Grace, Fergal , Herbert, Peter , Ratcliffe, John , New, Karl , Baker, Julien , Sculthorpe, Nicholas
- Date: 2015
- Type: Text , Journal article
- Relation: Physiological Reports Vol. 3, no. 1 (2015), p.
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- Description: Aging is associated with diffuse impairments in vascular endothelial function and traditional aerobic exercise is known to ameliorate these changes. High intensity interval training (HIIT) is effective at improving vascular function in aging men with existing disease, but its effectiveness remains to be demonstrated in otherwise healthy sedentary aging. However, the frequency of commonly used HIIT protocols may be poorly tolerated in older cohorts. Therefore, the present study investigated the effectiveness of lower frequency HIIT (LfHIIT) on vascular function in a cohort of lifelong sedentary (SED; n = 22, age 62.7 +/- 5.2 years) men compared with a positive control group of lifelong exercisers (LEX; n = 17, age 61.1 +/- 5.4 years). The study consisted of three assessment phases; enrolment to the study (Phase A), following 6 weeks of conditioning exercise in SED (Phase B) and following 6 weeks of low frequency HIIT in both SED and LEX (LfHIIT; Phase C). Conditioning exercise improved FMD in SED (3.4 +/- 1.5% to 4.9 +/- 1.1%; P < 0.01) such that the difference between groups on enrolment (3.4 +/- 1.5% vs. 5.3 +/- 1.4%; P < 0.01) was abrogated. This was maintained but not further improved following LfHIIT in SED whilst FMD remained unaffected by LfHIIT in LEX. In conclusion, LfHIIT is effective at maintaining improvements in vascular function achieved during conditioning exercise in SED. LfHIIT is a well-tolerated and effective exercise mode for reducing cardiovascular risk and maintaining but does not improve vascular function beyond that achieved by conditioning exercise in aging men, irrespective of fitness level.
- Authors: Grace, Fergal , Herbert, Peter , Ratcliffe, John , New, Karl , Baker, Julien , Sculthorpe, Nicholas
- Date: 2015
- Type: Text , Journal article
- Relation: Physiological Reports Vol. 3, no. 1 (2015), p.
- Full Text:
- Reviewed:
- Description: Aging is associated with diffuse impairments in vascular endothelial function and traditional aerobic exercise is known to ameliorate these changes. High intensity interval training (HIIT) is effective at improving vascular function in aging men with existing disease, but its effectiveness remains to be demonstrated in otherwise healthy sedentary aging. However, the frequency of commonly used HIIT protocols may be poorly tolerated in older cohorts. Therefore, the present study investigated the effectiveness of lower frequency HIIT (LfHIIT) on vascular function in a cohort of lifelong sedentary (SED; n = 22, age 62.7 +/- 5.2 years) men compared with a positive control group of lifelong exercisers (LEX; n = 17, age 61.1 +/- 5.4 years). The study consisted of three assessment phases; enrolment to the study (Phase A), following 6 weeks of conditioning exercise in SED (Phase B) and following 6 weeks of low frequency HIIT in both SED and LEX (LfHIIT; Phase C). Conditioning exercise improved FMD in SED (3.4 +/- 1.5% to 4.9 +/- 1.1%; P < 0.01) such that the difference between groups on enrolment (3.4 +/- 1.5% vs. 5.3 +/- 1.4%; P < 0.01) was abrogated. This was maintained but not further improved following LfHIIT in SED whilst FMD remained unaffected by LfHIIT in LEX. In conclusion, LfHIIT is effective at maintaining improvements in vascular function achieved during conditioning exercise in SED. LfHIIT is a well-tolerated and effective exercise mode for reducing cardiovascular risk and maintaining but does not improve vascular function beyond that achieved by conditioning exercise in aging men, irrespective of fitness level.
Evidence from randomised controlled trials did not support the introduction of dietary fat guidelines in 1977 and 1983 : A systematic review and meta-analysis
- Harcombe, Zoe, Baker, Julien, Cooper, Stephen, Davies, Bruce, Sculthorpe, Nicholas, DiNicolantonio, James, Grace, Fergal
- Authors: Harcombe, Zoe , Baker, Julien , Cooper, Stephen , Davies, Bruce , Sculthorpe, Nicholas , DiNicolantonio, James , Grace, Fergal
- Date: 2015
- Type: Text , Journal article
- Relation: Open Heart Vol. 2, no. 1 (2015), p. 1-9
- Full Text:
- Reviewed:
- Description: OBJECTIVES: National dietary guidelines were introduced in 1977 and 1983, by the US and UK governments, respectively, with the ambition of reducing coronary heart disease (CHD) by reducing fat intake. To date, no analysis of the evidence base for these recommendations has been undertaken. The present study examines the evidence from randomised controlled trials (RCTs) available to the US and UK regulatory committees at their respective points of implementation. METHODS: A systematic review and meta-analysis were undertaken of RCTs, published prior to 1983, which examined the relationship between dietary fat, serum cholesterol and the development of CHD. RESULTS: 2467 males participated in six dietary trials: five secondary prevention studies and one including healthy participants. There were 370 deaths from all-cause mortality in the intervention and control groups. The risk ratio (RR) from meta-analysis was 0.996 (95% CI 0.865 to 1.147). There were 207 and 216 deaths from CHD in the intervention and control groups, respectively. The RR was 0.989 (95% CI 0.784 to 1.247). There were no differences in all-cause mortality and non-significant differences in CHD mortality, resulting from the dietary interventions. The reductions in mean serum cholesterol levels were significantly higher in the intervention groups; this did not result in significant differences in CHD or all-cause mortality. Government dietary fat recommendations were untested in any trial prior to being introduced. CONCLUSIONS: Dietary recommendations were introduced for 220 million US and 56 million UK citizens by 1983, in the absence of supporting evidence from RCTs.
- Authors: Harcombe, Zoe , Baker, Julien , Cooper, Stephen , Davies, Bruce , Sculthorpe, Nicholas , DiNicolantonio, James , Grace, Fergal
- Date: 2015
- Type: Text , Journal article
- Relation: Open Heart Vol. 2, no. 1 (2015), p. 1-9
- Full Text:
- Reviewed:
- Description: OBJECTIVES: National dietary guidelines were introduced in 1977 and 1983, by the US and UK governments, respectively, with the ambition of reducing coronary heart disease (CHD) by reducing fat intake. To date, no analysis of the evidence base for these recommendations has been undertaken. The present study examines the evidence from randomised controlled trials (RCTs) available to the US and UK regulatory committees at their respective points of implementation. METHODS: A systematic review and meta-analysis were undertaken of RCTs, published prior to 1983, which examined the relationship between dietary fat, serum cholesterol and the development of CHD. RESULTS: 2467 males participated in six dietary trials: five secondary prevention studies and one including healthy participants. There were 370 deaths from all-cause mortality in the intervention and control groups. The risk ratio (RR) from meta-analysis was 0.996 (95% CI 0.865 to 1.147). There were 207 and 216 deaths from CHD in the intervention and control groups, respectively. The RR was 0.989 (95% CI 0.784 to 1.247). There were no differences in all-cause mortality and non-significant differences in CHD mortality, resulting from the dietary interventions. The reductions in mean serum cholesterol levels were significantly higher in the intervention groups; this did not result in significant differences in CHD or all-cause mortality. Government dietary fat recommendations were untested in any trial prior to being introduced. CONCLUSIONS: Dietary recommendations were introduced for 220 million US and 56 million UK citizens by 1983, in the absence of supporting evidence from RCTs.
High intensity interval training (HIIT) improves cardiorespiratory fitness (CRF) in healthy, overweight and obese adolescents : a systematic review and meta-analysis of controlled studies
- Martin-Smith, Rhona, Cox, Ashley, Buchan, Duncan, Baker, Julien, Grace, Fergal, Sculthorpe, Nicholas
- Authors: Martin-Smith, Rhona , Cox, Ashley , Buchan, Duncan , Baker, Julien , Grace, Fergal , Sculthorpe, Nicholas
- Date: 2020
- Type: Text , Journal article , Review
- Relation: International Journal of Environmental Research and Public Health Vol. 17, no. 8 (2020), p.
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- Description: Background: High Intensity Interval Training (HIIT) is a sustainable and effective method for improving Cardiorespiratory Fitness (CRF) in adolescents. HIIT is proven to produce equal or greater improvements in CRF when compared to moderate intensity continuous exercise (MICE) in adolescents. Methods: The studies included were considered eligible if: (1) Participants were adolescents (11–18 years old); (2) Examined changes in CRF measured either directly or indirectly; (3) Included a non-exercising control group or MICE comparison group; (4) Participants were matched at enrolment; (5) Reported HIIT protocol information; (6) Provided HIIT intensity. A meta-analysis was conducted to determine the effect of HIIT on CRF. Meta-regression and moderator analyses were performed out to quantitatively examine moderators of protocol design on CRF improvements. Results: HIIT displays a moderate effect to improve CRF (g = 0.86, 95% CI 0.518–1.106, p < 0.001). Neither study duration (weeks), nor total or weekly accumulated HIIT volume (min) displayed any significant moderation effect on pooled improvement on CRF (p > 0.05). Conclusions: HIIT is an effective method to improve CRF in adolescents, irrespective of body composition. Notably, meta regression analysis identified that prolonged high volume HIIT programs are similarly effective to short term low volume HIIT programs. This becomes of particular interest for those involved in school curricula, where short HIIT exercise may provide a pragmatic adjunct to the health benefits of Physical Education (PE) lessons. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
- Authors: Martin-Smith, Rhona , Cox, Ashley , Buchan, Duncan , Baker, Julien , Grace, Fergal , Sculthorpe, Nicholas
- Date: 2020
- Type: Text , Journal article , Review
- Relation: International Journal of Environmental Research and Public Health Vol. 17, no. 8 (2020), p.
- Full Text:
- Reviewed:
- Description: Background: High Intensity Interval Training (HIIT) is a sustainable and effective method for improving Cardiorespiratory Fitness (CRF) in adolescents. HIIT is proven to produce equal or greater improvements in CRF when compared to moderate intensity continuous exercise (MICE) in adolescents. Methods: The studies included were considered eligible if: (1) Participants were adolescents (11–18 years old); (2) Examined changes in CRF measured either directly or indirectly; (3) Included a non-exercising control group or MICE comparison group; (4) Participants were matched at enrolment; (5) Reported HIIT protocol information; (6) Provided HIIT intensity. A meta-analysis was conducted to determine the effect of HIIT on CRF. Meta-regression and moderator analyses were performed out to quantitatively examine moderators of protocol design on CRF improvements. Results: HIIT displays a moderate effect to improve CRF (g = 0.86, 95% CI 0.518–1.106, p < 0.001). Neither study duration (weeks), nor total or weekly accumulated HIIT volume (min) displayed any significant moderation effect on pooled improvement on CRF (p > 0.05). Conclusions: HIIT is an effective method to improve CRF in adolescents, irrespective of body composition. Notably, meta regression analysis identified that prolonged high volume HIIT programs are similarly effective to short term low volume HIIT programs. This becomes of particular interest for those involved in school curricula, where short HIIT exercise may provide a pragmatic adjunct to the health benefits of Physical Education (PE) lessons. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
Exercise, science and designer doping : Traditional and emerging trends
- Graham, M. R., Davies, Bruce, Grace, Fergal, Baker, Julien
- Authors: Graham, M. R. , Davies, Bruce , Grace, Fergal , Baker, Julien
- Date: 2012
- Type: Text , Journal article
- Relation: Journal of Sports Medicine and Doping Studies Vol. 2, no. 3 (2012), p.
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- Description: The list of doping agents is enormous, and for the majority, any beneficial sporting effect is contentious. WADA and UK Anti-Doping have difficulty detecting the peptide hormones, Growth Hormone (GH), insulin and Erythropoietin (Epo), because they require blood analysis. Only in the last two years has an athlete been convicted of taking GH, which is still being used as a doping agent because the window for detection is so brief. This positive test was not contested, which suggests that science may be winning the war on drugs. Athletes appear to have ceased taking insulin, because of its life-threatening acute effects, and in recent years no adverse analytical findings have been reported for this drug. “Older” doping agents, which are known to enhance performance in sport, include testosterone and their derivatives, anabolic steroids. The pharmaceutical industry continues to manufacture new medicines, pushing back the boundaries in combating wasting disease states and the ageing process, but is inadvertently producing the latest generation of doping agents. This will challenge anti-doping scientists. WADA’s banned list also includes insulin-like growth factor-1, fibroblast growth factors, hepatocyte growth factor, mechano growth factors, platelet-derived growth factor, vascular-endothelial growth factor which may promote muscle, tendon or ligament development, vascularisation, energy utilisation, regenerative capacity and fibre type. Athletes will use whatever they believe works, but can only use what is available. Internet companies offer these anabolic products that but their veracity cannot be proven. There are questions that need to be answered? Are these products available to athletes, do they enhance performance, are athletes really taking them and are they so difficult to detect. The internet has made them available to anyone with a credit card and it appears that if they are cycled correctly, unless an athlete is caught in possession of them, the opportunity of proving a case of doping is almost impossible.
- Authors: Graham, M. R. , Davies, Bruce , Grace, Fergal , Baker, Julien
- Date: 2012
- Type: Text , Journal article
- Relation: Journal of Sports Medicine and Doping Studies Vol. 2, no. 3 (2012), p.
- Full Text:
- Reviewed:
- Description: The list of doping agents is enormous, and for the majority, any beneficial sporting effect is contentious. WADA and UK Anti-Doping have difficulty detecting the peptide hormones, Growth Hormone (GH), insulin and Erythropoietin (Epo), because they require blood analysis. Only in the last two years has an athlete been convicted of taking GH, which is still being used as a doping agent because the window for detection is so brief. This positive test was not contested, which suggests that science may be winning the war on drugs. Athletes appear to have ceased taking insulin, because of its life-threatening acute effects, and in recent years no adverse analytical findings have been reported for this drug. “Older” doping agents, which are known to enhance performance in sport, include testosterone and their derivatives, anabolic steroids. The pharmaceutical industry continues to manufacture new medicines, pushing back the boundaries in combating wasting disease states and the ageing process, but is inadvertently producing the latest generation of doping agents. This will challenge anti-doping scientists. WADA’s banned list also includes insulin-like growth factor-1, fibroblast growth factors, hepatocyte growth factor, mechano growth factors, platelet-derived growth factor, vascular-endothelial growth factor which may promote muscle, tendon or ligament development, vascularisation, energy utilisation, regenerative capacity and fibre type. Athletes will use whatever they believe works, but can only use what is available. Internet companies offer these anabolic products that but their veracity cannot be proven. There are questions that need to be answered? Are these products available to athletes, do they enhance performance, are athletes really taking them and are they so difficult to detect. The internet has made them available to anyone with a credit card and it appears that if they are cycled correctly, unless an athlete is caught in possession of them, the opportunity of proving a case of doping is almost impossible.
An evaluation of temporal and club angle parameters during golf swings using low cost video analyses packages
- Hunter, Henry, Ugbolue, Ukadike, Sorbie, Graeme, Lam, Wing-Kai, Grace, Fergal, Dello Iacono, Antonio, Liang, Minjun, Dutheil, Frederic, Gu, Yaodong, Baker, Julien
- Authors: Hunter, Henry , Ugbolue, Ukadike , Sorbie, Graeme , Lam, Wing-Kai , Grace, Fergal , Dello Iacono, Antonio , Liang, Minjun , Dutheil, Frederic , Gu, Yaodong , Baker, Julien
- Date: 2022
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 12, no. 1 (2022), p.
- Full Text:
- Reviewed:
- Description: The purpose of this study was to compare swing time and golf club angle parameters during golf swings using three, two dimensional (2D) low cost, Augmented-Video-based-Portable-Systems (AVPS) (Kinovea, SiliconCoach Pro, SiliconCoach Live). Twelve right-handed golfers performed three golf swings whilst being recorded by a high-speed 2D video camera. Footage was then analysed using AVPS-software and the results compared using both descriptive and inferential statistics. There were no significant differences for swing time and the golf phase measurements between the 2D and 3D software comparisons. In general, the results showed a high Intra class Correlation Coefficient (ICC > 0.929) and Cronbach’s Coefficient Alpha (CCA > 0.924) reliability for both the kinematic and temporal parameters. The inter-rater reliability test for the swing time and kinematic golf phase measurements on average were strong. Irrespective of the AVPS software investigated, the cost effective AVPS can produce reliable output measures that benefit golf analyses. © 2022, Crown.
- Authors: Hunter, Henry , Ugbolue, Ukadike , Sorbie, Graeme , Lam, Wing-Kai , Grace, Fergal , Dello Iacono, Antonio , Liang, Minjun , Dutheil, Frederic , Gu, Yaodong , Baker, Julien
- Date: 2022
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 12, no. 1 (2022), p.
- Full Text:
- Reviewed:
- Description: The purpose of this study was to compare swing time and golf club angle parameters during golf swings using three, two dimensional (2D) low cost, Augmented-Video-based-Portable-Systems (AVPS) (Kinovea, SiliconCoach Pro, SiliconCoach Live). Twelve right-handed golfers performed three golf swings whilst being recorded by a high-speed 2D video camera. Footage was then analysed using AVPS-software and the results compared using both descriptive and inferential statistics. There were no significant differences for swing time and the golf phase measurements between the 2D and 3D software comparisons. In general, the results showed a high Intra class Correlation Coefficient (ICC > 0.929) and Cronbach’s Coefficient Alpha (CCA > 0.924) reliability for both the kinematic and temporal parameters. The inter-rater reliability test for the swing time and kinematic golf phase measurements on average were strong. Irrespective of the AVPS software investigated, the cost effective AVPS can produce reliable output measures that benefit golf analyses. © 2022, Crown.
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