The effect of an anabolic steroid and training on the skeletal muscle of the horse

1) Resting Study: Nandrolone phenylpropionats (therapeutic dose) was administered i.m. to 4 healthy, mature castrate horses at weekly intervals for 7 weeks. Measurement of body weight and nitrogen excretion failed to show a consistent anabolic effect. Examination of biopsies from the semitendinosus and biceps femoris muscles showed no alteration in water content or glycogen concentration with treatment. Similarly no changes were found in the activities of the following enzymes: lactate dehydrogenase, aldolase, citrate synthase, aspartate aminotransferase, alanine aminotransferase and 3-hydroxyacy1 CoA dehydrogenase. However a significant increase in the proportion of fast twitch low oxidative fibres of the biceps femoris was observed. The occurrence of some components of stallion behaviour in geldings was taken to reflect a residual androgenic activity in the compound. 2) Exercise Study: The effect of nandrolone phenylpropionate was investigated in 6 Thoroughbred geldings which were involved in a training programme. The study was conducted on a crossover basis, each animal acting as its own control. 3) Acute Exercise Study: Ca) Electron microscopy study. The effect of strength and endurance exercise on skeletal muscle ultrastructure was investigated in 3 Thoroughbreds and 1 Heavy Hunter using various fixation procedures. The resting ultrastructure was similar to that of other species. After strength exercise disruption was noted in all samples. Disruption was also noted after endurance exercise but only in samples fixed in osmium tetroxide. (b) netabolites . The 6 Thoroughbred horses of the exercise study were galloped over various distances 506m, 1025m, 1600m and 3620m. Glycogen depletion was significantly greater in the 1025m and 1600m than in the 506m trial. Pyruvate concentrations did not alter significantly with exercise. Lactate production over the 3 shorter distances was significantly greater than the production over the 3620m trial. There was no difference at any stage, in any parameter measured, between control and anabolic group. In conclusion, these studies have shown that at a high therapeutic dose, nandrolone phenylpropionate had little effect on the skeletal musculature of both resting and exercising Thcroughbreo horses. The only notable effect was the alteration in histochemical profile of the biceps femoris muscle. The relevance of this change to the racing performenes of the whole animal is questionable, Both the electron microscopical study and the investigation into the utilisation of fuels over various distances provides some preliminary results which serve as a good basis on which to continue. (Abstract shortened by ProQuest.)

Exercise and ghrelin. A narrative overview of research

Since its discovery in 1999, ghrelin has been implicated in a multiplicity of physiological activities. Most notably, ghrelin has an important influence on energy metabolism and after the identification of its potent appetite stimulating effects ghrelin has been termed the ‘hunger hormone.’ Exercise is a stimulus which has a significant impact on energy homeostasis and consequently a substantial body of research has investigated the interaction between exercise and ghrelin. This narrative review provides an overview of research relating to the acute and chronic effects of exercise on circulating ghrelin (acylated, unacylated and total). To enhance study comparability, the scope of this review is limited to research undertaken in adult humans and consequently studies involving children and animals are not discussed. Although there is significant ambiguity within much of the early research, our review suggests that acute exercise transiently interferes with the production of acylated ghrelin. Furthermore, the consensus of evidence indicates that exercise training does not influence circulating ghrelin independent of weight loss. Additional research is needed to verify and extend the available literature, particularly by uncovering the mechanisms governing acute exercise-related changes and characterising responses in other populations such as females, older adults, and the obese

An evaluation of low volume high-intensity intermittent training (HIIT) for health risk reduction in overweight and obese men

Both sprint interval training (SIT) and high-intensity intermittent training (HIIT) have been described as time-efficient strategies for inducing favourable metabolic and cardiorespiratory adaptations in healthy and diseased participants. BACKGROUND: To date, little attention has been given to profiling the potential health benefits of HIIT or modified HIIT training within overweight and obese cohorts with particular focus on inflammation. Within this pilot trial, we tested the hypothesis that 6 sessions of HIIT performed over 2 weeks with 1-2 days’rest would improve aerobic capacity, glucose metabolism and inflammatory profile in an overweight and obese male cohort. Additionally, we profiled the potential health benefits of 4 HIIT sessions performed over the same period. METHODS: 18 overweight or obese males (BMI = 31.2 ± 3.6; V̇O2 = 30.3 ± 4.4 ml.kg.min-1) were studied before and 72 h after HIIT. Training sessions consisted of 10 x 1 min intervals at 90% HRpeak separated by 1 min recovery periods. Exercise was performed either 6 (group 1, n = 8) or 4 (group 2, n = 10)times over a 2 week period. RESULTS: After training no changes were detected from baseline for body composition, aerobic capacity, glucose metabolism or inflammatory profile(p > 0.05) in either group. CONCLUSION: Both 6 and 4 sessions of HIIT performed over a 2-week period are ineffective in improving selected health markers within an overweight and obese cohort

The impact of high intensity intermittent exercise on resting metabolic rate in healthy males

Introduction High-intensity intermittent exercise training (HIT) may favourably alter body composition despite low training volumes and predicted energy expenditure (EE). Purpose To characterise the acute impact of two common HIT protocols on EE and post-exercise oxygen consumption (11 h EPOC). Methods Oxygen consumption (l min−1), respiratory exchange ratio (RER) and EE were measured in nine healthy, lean males over 12 h under three conditions: control (CON), HIT1 (10 × 1 min high-intensity cycling bouts followed by 1 min rest) and HIT2 (10 × 4 min high-intensity cycling bouts followed by 2 min rest). Results Total exercise period EE during HIT1 (1,151 ± 205 kJ) (mean ± SD) was significantly lower than HIT2 (2,788 ± 322 kJ; p < 0.001). EE within the 60 min after exercise was significantly albeit marginally higher after HIT1 (388 ± 44 kJ; p = 0.02) and HIT2 (389 ± 39 kJ; p = 0.01) compared with CON (329 ± 39 kJ), with no difference between exercise conditions (p = 0.778). RER during this period was significantly lower in HIT1 (0.78 ± 0.06; p = 0.011) and HIT2 (0.76 ± 0.04; p = 0.004) compared with CON (0.87 ± 0.06). During the ‘slow phase’ of EPOC (1.25–9.75 h), there were no significant differences in EE (p = 0.07) or RER (p = 0.173) between trials

Do overweight and obese individuals demonstrate impaired thermoregulatory adaptation to six weeks of studio cycling training: a pilot study

High intensity interval training (HIIT) is effective at improving health markers in groups at risk of cardiovascular and metabolic disease. Studio cycling may offer a platform for HIIT in the community, however little is know about how increased adiposity influences thermal control during HIIT and the effect this may have on overweight patients who are new to exercise. The purpose of this pilot study was to investigate the thermal adaptation in response to studio based group HIIT in sedentary overweight adults

Group studio cycling is an effective intervention to improve cardio-metabolic health in overweight sedentary individuals

Group studio cycling is an effective intervention to improve cardio-metabolic health in overweight sedentary individual

Cross-sectional surveillance study to phenotype lorry drivers’ sedentary behaviours, physical activity and cardio-metabolic health

Objectives Elevated risk factors for a number of chronic diseases have been identified in lorry drivers. Unhealthy lifestyle behaviours such as a lack of physical activity (PA) and high levels of sedentary behaviour (sitting) likely contribute to this elevated risk. This study behaviourally phenotyped UK lorry drivers’ sedentary and non-sedentary behaviours during workdays and non-workdays and examined markers of drivers cardio-metabolic health.Setting A transport company from the East Midlands, UK. Participants A sample of 159 male heavy goods vehicle drivers (91% white European; (median (range)) age: 50 (24, 67) years) completed the health assessments. 87 (age: 50.0 (25.0, 65.0); body mass index (BMI): 27.7 (19.6, 43.4) kg/m2) provided objective information on sedentary and non-sedentary time.Outcomes Participants self-reported their sociodemographic information. Primary outcomes: sedentary behaviour and PA, assessed over 7 days using an activPAL3 inclinometer. Cardio-metabolic markers included: blood pressure (BP), heart rate, waist circumference (WC), hip circumference, body composition and fasted capillary blood glucose, triglycerides, high-density lipopreotein cholesterol, low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) levels. These cardio-metabolic markers were treated as secondary outcomes.Results Lorry drivers presented an unhealthy cardio-metabolic health profile (median (IQR) systolic BP: 129 (108.5, 164) mm Hg; diastolic BP: 81 (63, 104) mm Hg; BMI: 29 (20, 47) kg/m2; WC: 102 (77.5, 146.5) cm; LDL-C: 3 (1, 6) mmol/L; TC: 4.9 (3, 7.5) mmol/L). 84% were overweight or obese, 43% had type 2 diabetes or prediabetes and 34% had the metabolic syndrome. The subsample of lorry drivers with objective postural data (n=87) accumulated 13 hours/day and 8 hours/day of sedentary behaviour on workdays and non-workdays (p&lt;0.001), respectively. On average, drivers accrued 12 min/day on workdays and 6 min/day on non-workdays of moderate-to-vigorous PA (MVPA).Conclusion Lorry drivers demonstrate a high-risk cardio-metabolic profile and are highly sedentary and physically inactive. Interventions to reduce sitting and increase MVPA during breaks and leisure time to improve cardio-metabolic health are urgently needed. Educational programmes to raise awareness about diet and exercise are recommended.%U http://bmjopen.bmj.com/content/bmjopen/7/6/e013162.full.pd

Appetite regulatory hormone responses on the day following a prolonged bout of moderate-intensity exercise

Exercise increases energy expenditure however acutely this does not cause compensatory changes in appetite or food intake. This unresponsiveness contrasts the rapid counter-regulatory changes seen after food restriction. The present investigation examined whether corrective changes in appetite-regulatory parameters occur after a time delay, namely, on the day after a single bout of exercise. Nine healthy males completed two, two-day trials (exercise & control) in a random order. On the exercise trial participants completed 90 min of moderate-intensity treadmill running on day one (10:30–12:00 h). On day two appetite-regulatory hormones and subjective appetite perceptions were assessed frequently in response to two test meals provided at 08:00 and 12:00 h. Identical procedures occurred in the control trial except no exercise was performed on day one. Circulating levels of leptin were reduced on the day after exercise (AUC 5841 ± 3335 vs. 7266 ± 3949 ng− 1·mL− 1 · 7 h, P = 0.012). Conversely, no compensatory changes were seen for circulating acylated ghrelin, total PYY, insulin or appetite perceptions. Unexpectedly, levels of acylated ghrelin were reduced on the exercise trial following the second test meal on day two (AUC 279 ± 136 vs. 326 ± 136 pg− 1·mL− 1 · 3 h, P = 0.021). These findings indicate that short-term energy deficits induced by exercise initially prompt a compensatory response by chronic but not acute hormonal regulators of appetite and energy balance. Within this 24 h time-frame however there is no conscious recognition of the perturbation to energy balance

The extended growth of graphene oxide flakes using ethanol CVD

We report the extended growth of Graphene Oxide (GO) flakes using atmospheric pressure ethanol Chemical Vapor Deposition (CVD). GO was used to catalyze the deposition of carbon on substrate in the ethanol CVD with Ar and H2 as carrier gases. Raman, SEM, XPS 10 and AFM characterized the growth to be reduced GO (RGO) of <5 layers. This new grown RGO possesses lower defect density with larger and increased distribution of sp2 domains than chemically-reduced RGO. Furthermore this method without optimization reduces relative standard deviation of electrical conductivity between chips, from 80.5% to 16.5%, enabling RGO to be used in practical electronic devices