No description available.

Training studies involving competitive runners and road cyclists have shown substantial gains in sprint and endurance performance when sessions of high-intensity interval training were added to their usual training in the competitive phase of a season. Further research has shown large performance benefits in sprint and endurance power (7 - 9%) when cyclists combined explosive single-leg jumps with cycling-specific high-intensity interval training during a competitive season. The aim of the present study was to assess the contribution of the jumps to the gains in performance in competitive cyclists in a randomized control trial.The training protocol for the control group was based on previous experimental work in which the control group (n=8) completed cycle specific interval training followed by a series of explosive single-leg jumps. The experimental group (n=7) carried out the same cycle specific interval training but did not participate in the explosive single-leg jumps. While the current study did not use a true control group, the investigation was carried out in the knowledge that a combination of high intensity interval cycling and explosive single-leg jumps causes changes positive changes in performance. Participants took part in 10 x 30-min sessions consisting four sets of high intensity intermittent cycling (4 x 30-s maximum efforts at 50 - 60 min-1 alternating with 30-s recovery). Between each set of 4 x 30 s sprints the control (ballistic) group carried out one set of explosive single-leg jumps (20 for each leg), while the experimental (continuous) group cycled for 20 s at 50 - 60 min-1.Before and after the training period all cyclists completed an incremental peak power test for assessment of VO2max, lactate threshold, exercise economy and peak power, a 30 s Wingate sprint test and a 20 km time-trial. Relative to the control group the percent mean changes (±90% confidence limits) in the experimental group were: power at 4-mM lactate, -4.2 (±6.3); VO2max, -3.1 (±3.7); mean time-trial power, -0.7 (± 4.7); peak incremental power, -1.7; (±5.0); power at 80% max heart rate, -2.8; (±5.6); Wingate peak power, -4.2; (±7.8). We conclude that high-intensity training may improve performance but the combination of high-intensity training and explosive resistance training in the competitive phase is likely to produce greater gains in trained cyclists than high intensity cycling alone.

abstract: Heart failure is a major worldwide health concern and is the leading cause of hospitalization among elderly Americans. Approximately 50% of those diagnosed with heart failure have heart failure with preserved ejection fraction (HFPEF). HFPEF presents a therapeutic dilemma because pharmacological strategies that are effective for the treatment of heart failure and reduced ejection fraction have failed to show benefit in HFPEF. Long term moderate intensity exercise programs have been shown to improve diastolic function in patients HFPEF. High intensity interval training (HIIT) has been shown to improve diastolic function in patients with heart failure and reduced ejection fraction. However, the effects of high intensity interval training in patients with HFPEF are unknown. Fourteen patients with HFPEF were randomized to either: (1) a novel program of high-intensity aerobic interval training (n = 8), or (2) a commonly prescribed program of moderate-intensity (MOD) aerobic exercise training (n = 6). Before and after four weeks of exercise training, patients underwent a treadmill graded exercise test for the determination of peak oxygen uptake (VO2peak), a brachial artery reactivity test for assessment of endothelium-dependent flow-mediated dilation (BAFMD), aortic pulse wave velocity assessment as an index of vascular stiffness and two-dimensional echocardiography for assessment of left ventricular diastolic and systolic function. I hypothesized that (1) high-intensity aerobic interval training would result in superior improvements in FMD, aortic pulse wave velocity, VO2peak, diastolic function and, (2) changes in these parameters would be correlated with changes in VO2peak. The principal findings of the study were that a one month long high intensity interval training program resulted in significant improvements in diastolic function as measured by two-dimensional echocardiography [pre diastolic dysfunction (DD) grade - 2.13 + 0.4 vs. post DD grade - 1.25 + 0.7, p = 0.03]. The left atrial volume index was reduced in the HIIT group compared to MOD ( - 4.4 + 6.2 ml/m2 vs. 5.8 + 10.7 ml/m2, p = 0.02). Early mitral flow (E) improved in the HIIT group (pre - 0.93 + 0.2 m/s vs. post - 0.78 + 0.3 m/s, p = 0.03). A significant inverse correlation was observed between change in BAFMD and change in diastolic dysfunction grade (r = - 0.585, p = 0.028) when all the data were pooled. HIIT appears to be a time-efficient and safe strategy for improving diastolic function in patients with heart failure and preserved ejection fraction. These data may have implications for cardiovascular risk reduction in this population. / Dissertation/Thesis / Ph.D. Exercise and Wellness 2012

abstract: The winter holiday period has been highlighted as a major risk period for weight gain due to excess caloric intake in the form of fat and sugar. Furthermore, diets high in fat and sugar have been implicated in the pathogenesis of diabetes and cardiovascular disease. Exercise aids in the prevention of weight/fat gain, and prevents deleterious changes in cardiometabolic function. The objective of this study was to examine the effects of a fat-sugar supplemented diet, with and without two different exercise training protocols, on body composition, glycemic control and other markers of cardiovascular disease in an at-risk population of overweight and obese males. Twenty-seven, healthy overweight/obese (BMI >25 kg/m2) males were fed 2 donuts per day, 6 days/week, for four weeks, while maintaining their current diet. In addition, all subjects were randomized to one of the following conditions: sedentary control, 1,000 kcal/week moderate-intensity continuous training (MICT) (50% of peak oxygen consumption), or 1,000 kcal/week high-intensity interval training (HIIT) (90-95% of peak heart rate). Supervised exercise training was performed 4 days/week on a cycle ergometer. Changes in body weight and composition, endothelial function, arterial stiffness, glycemic control, blood lipids and cardiorespiratory fitness (CRF) were assessed before and after the intervention. Body weight, lean mass and visceral fat increased significantly in HIIT (p<0.05) and were unchanged in MICT. There was a trend for a significant increase in body weight (p=0.07) and lean mass (p=0.11) in control. Glycemic control during the 2-h OGTT improved significantly in MICT and control, with no change in HIIT. Hepatic insulin resistance index (IRI) and 30-min insulin during the OGTT improved significantly after MICT and worsened following control (p=0.03), while HIIT was unchanged. CRF increased significantly in both HIIT and MICT, with no change in control (p<0.001). There were no significant changes in other markers of cardiovascular disease. The addition of a fat-sugar supplement (~14,500 kcal) over a 4-week period was not sufficient to induce deleterious changes in body composition and cardiometabolic health in overweight/obese young males. Exercise training did not afford overweight/obese males additional health benefits, with the exception of improvements in fitness and hepatic IRI. / Dissertation/Thesis / Doctoral Dissertation Physical Activity, Nutrition and Wellness 2016

No description available.

The aim of this master thesis is to evaluate the influence of a six-week HIIT (High intensity interval training) on body composition and both aerobic and anaerobic performance. A group of 9 men aged 28-51 years was gathered and who followed an exact six-week training programme according to the chosen hypothesis. The results of our study show that the chosen six-week programme led to statistically significant (p < 0,05) changes in body weight (kg), BMI (kg/m2 ), in FEV (l), and ANC/kg (J/kg). Changes in the other parameters were statistically not significant. Taking into account the size of group (n=9) we conclude that mainly effects on the individual level were attained.

Background: Repeated sprint training in hypoxia has shown to be superior to training in normoxia. However, both natural and simulated altitude training are strategies that are not always accessible and expensive due to traveling or the need for advanced equipment. A possible way of simulating hypoxic conditions is to administer carbon monoxide (CO) prior to training as it has been shown to reduce the oxygen transport and delivery to the muscle similar to systemic hypoxia. It is therefore hypothesized that inhaling a small bolus of CO prior to repeated-sprint exercise will potentiate the acute physiological responses during the training, thus induce performance improvements associated with repeated sprint ability compared to placebo control. Methods: 23 endurance-trained individuals (18 men and 5 women), age 33.2 ± 6.9 years, body mass 78.3 ± 11.0 kg, height 180.7 ± 7.3 cm, performed a 3-week supervised repeated sprint exercise protocol on electromagnetically braked cycle ergometers. A repeated sprint ability test was conducted pre-and post-training intervention. Participants were randomly assigned to either inhaling CO (INCO group) or inhaling a sham gas (NOCO group). Analysis of covariance (ANCOVA) was conducted to determine statistical significance by controlling for pre-test values. Results: Periodic inhalation of CO prior to repeated sprint exercise led a medium, significant difference in mean power decrement (INCO -2.63%, NOCO 8%; p &lt;0.05, ηp2 = 0.19) and fatigue index (INCO 0.28%, NOCO 8.2%; p &lt;0.05, ηp2 = 0.24) compared to sham gas, despite that both groups increased in number of sprints (INCO 16.58%, NOCO 27.60%; p &lt;0.05; ηp2 = 0.71) with no difference between groups. Conclusion: Our findings in this study showed a positive effect on an improved ability to sustain power output during repeated sprints when periodic inhalation of CO is administered. Therefore, it is suggested that periodic inhalation of CO prior to repeated sprint exercise might be a nuanced way to induce favorable physiological adaptations, thus improving performance associated with repeated sprint ability.

Purpose: To examine the effects of 28 days of β-hydroxy-β-methylbutyrate free acid (HMB) and high-intensity interval training (HIIT) on maximal oxygen consumption (VO2peak), ventilatory threshold (VT), respiratory compensation point (RCP) and time to exhaustion (Tmax) in collegeaged men and women. Methods: Healthy men and women (n=34, age and VO2peak= 22.7+3.1yr and 39.3+5.0 mL. kg-1.min-1, respectively) participated in this study. All participants completed a series of tests prior and subsequent to treatment. A maximal oxygen consumption test was performed on a cycle ergometer to assess VO2peak, Tmax, VT, and RCP. The peak power output (Ppeak), power at VT (PVT) and power at RCP (PRCP) were also recorded from this test. Twenty-six subjects completed 12 HIIT (80-120% maximal workload) exercise sessions consisting of 5-6 bouts of a 2:1 minute cycling work to rest ratio protocol over a four-week period, while eight served as controls (CTL). In double-blind fashion, the HIIT groups were assigned into either a placebo (HIIT) or 3g per day of HMB (HMB-HIIT). Body composition was measured with dual energy x-ray absorptiometry (DEXA). Outcomes were assessed by ANCOVA with posttest means adjusted for pretest differences. Results: The HMB-HIIT intervention showed significant (p & lt 0.05) gains in VO2peak, VT, and PVT versus the CTL and HIIT group. Both HIIT and HMB-HIIT treatment groups demonstrated significant (p < 0.05) improvement over CTL for Ppeak, Tmax, RCP, and PRCP with no significant difference between the treatment groups. There were no significant differences observed for any measures of body composition. An independent-samples t-test confirmed that there were no significant differences between the training volumes for the HIIT and HMB-HIIT groups. Conclusion: These findings suggest that the addition of HMB supplementation may result in greater changes in VO2peak and VT than HIIT alone. Therefore, in college-aged men and women, the use of HMB supplementation may enhance the benefits of HIIT on aerobic performance measures.

No description available.

No description available.