The primary focus of this study was to determine basal levels of myogenic (MRF4, myogenin, MyoD), proteolytic (FOXO3A, atrogin-1, MuRF-1), myostatin, and mitochondrial (PGC-1α & Tfam) mRNA in elderly women before and after aerobic training. This approach was taken to gain insight into the molecular adaptations associated with our observed increases in whole muscle cross sectional area (CSA) (11%, p<0.05), knee extensor muscle function (25%, p<0.05) and aerobic capacity (30%, p<0.05) with training. Nine elderly women (71±2y) underwent muscle biopsies obtained from the vastus lateralis before and after 12-weeks of aerobic training on a cycle ergometer. Post training biopsy samples were acquired 48 hours after the last exercise session. Aerobic training reduced (p < 0.05) resting levels of MRF4 by 25% while myogenin showed a trend to decrease (p = 0.09) after training. FOXO3A expression was 27% lower (p < 0.05) while atrogin-1 and MuRF-1 were unaltered after training. Additionally, myostatin gene expression was decreased (p < 0.05) by 57% after training. Lastly, aerobic training did not alter PGC-1α or Tfam mRNA. These findings suggest that aerobic training alters basal transcript levels of growth related genes in skeletal muscle of older women. Further, the reductions in FOXO3A and myostatin indicate the aerobic training induced muscle hypertrophy in older women may be due to alterations in proteolytic machinery. / School of Physical Education, Sport, and Exercise Science

The aim of this research was to develop a novel multi-function exercise system for use in a broad range of applications. Market research indicates that the demand for aerobic and anaerobic exercise devices will continue to grow with the introduction of government physical activity guidelines and increased social pressure regarding health related issues. A detailed investigation of the basic exercise science fundamentals and training methodologies was conducted in order to develop a system which would provide efficient and effective training related stimuli for improving fitness. The generation, storage and utilisation of actual and virtual load and velocity profiles for use in the development of original training modes was identified as an important area of the research. The proposed solution utilises an electromechanical programmable motion control system which provides all of the necessary exercise modalities defined in the system specification. This system combines existing industrial servo drive technology with proprietary software and database facilities to provide a step change in functionality, ease of use and safety for all users. Development of these hardware and software elements was supported by the creation of a series of system models at the initial stages of the research using the computer integrated manufacturing open systems architecture (CIMOSA) modelling approach. These diagrams were an invaluable resource during the concept generation and refinement processes and have clearly demonstrated the cross-discipline applications of such formalised modelling techniques. Validation and reliability data collected during prototype testing indicated that the exercise motion generation capabilities and performance measurement facilities were comparable to existing isokinetic dynamometer equipment. Additional subject testing produced results with peak output values and parameter trends which correlated closely to those determined during clinical and academic research. These experimental results suggest that the modular exercise system could be a valuable tool for the collection of research data to be used in support of current and future training theories.

Previous reports have demonstrated that children’s physical activity is typically intermittent in nature. Accelerometers are reliable and valid tools for quantifying the pattern of activity in children. However, in order to interpret accelerometer output it is necessary to apply appropriate accelerometer thresholds for classifying physical activity intensity. Currently multiple accelerometer thresholds are available in the literature and it is unclear which are the most appropriate or whether thresholds should be sample specific. Additionally, there is little information regarding how the pattern of activity in children varies across groups and how activity patterns relate to health. The overall aim of the thesis was to describe the pattern of habitual physical activity, using objectively-measured physical activity data, in relation to health outcomes in pre-adolescent boys. The first objective was to characterize the pattern of boys’ habitual physical activity, using objectively-measured physical activity data. The second objective was to investigate the relationship between habitual physical activity and specific aspects of the activity pattern and health outcomes in boys. The final objective was to investigate the effects of continuously- versus intermittently- accumulated physical activity on acute health outcomes in boys, using an intermittent activity protocol based on the measured pattern of habitual activity in boys. The first four studies used a sample of 54 boys, aged 8 to 10 years. The final study used a different sample of 10 boys, aged 9 to 11 years. Both samples were from the county of Devon, UK. The first study of this thesis established sample-specific accelerometer-intensity thresholds through calibration research with ActiGraph accelerometers (counts•2s-1) in boys. The second study in the thesis demonstrated that relationships between time accumulated at different activity intensities and health (fatness, peak oxygen consumption and resting blood pressure) in boys were similar irrespective of whether sample-specific or published thresholds were employed as long as the threshold was at least equivalent to a brisk walk (i.e. >4 METs). However, the prevalence of children reported as meeting activity guidelines did differ according to thresholds employed. Study three showed that, despite little difference between overweight and normal weight boys in overall activity, time spent sedentary and minutes of light, moderate and vigorous intensity activity accumulated, aspects of the activity pattern (frequency, intensity and duration of ≥4 s (short) and ≥5-min (long) bouts of ≥light, ≥moderate, ≥vigorous and ≥hard intensity activity) differed by weight status. Overweight boys accumulated fewer and shorter bouts of activity, particularly sustained bouts of activity which were of moderate intensity or greater. Study four examined the relationship between activity pattern and health in boys further, focusing on body fatness, aerobic fitness, blood pressure and microvascular function. Results demonstrated that summary measures of activity were negatively related to body fatness, and positively related with both aerobic fitness (i.e., total, moderate, vigorous and hard activity) and endothelial function (i.e., total and light activity). Time spent sedentary was negatively related to endothelial function. The frequency and duration of activity bouts of ≥moderate intensity and the intensity of all activity bouts (i.e., ≥light intensity) were most important for body fatness and aerobic fitness. The frequency of all bouts (short and long) of at least light intensity was most important for endothelial health. Finally, study five moved away from chronic measures of health and examined the acute physiological effects of the recommended daily amount of physical activity (60 minutes of physical activity of ≥moderate intensity) on postprandial lipaemia and microvascular function in boys the following day. Furthermore, the study aimed to assess whether the effects differed depending on whether the activity was accumulated continuously or in a manner more similar to the children’s typical activity patterns identified in studies 3 and 4. In contrast to findings from adolescents and adults, 60 minutes of >moderate intensity activity did not impact on postprandial lipaemia or microvascular function the following day in healthy, active boys, regardless of how it was accumulated. The results of the present thesis indicate that aspects of the activity pattern are significantly related to health in boys and differ according to type of day and weight status. Furthermore, the benefits of sporadically-accumulated activity are equally as strong as continuously-accumulated activity to body fatness, aerobic fitness and endothelial health in boys. Since children typically accumulate short, intermittent bouts of activity, the promotion of sporadic activity (i.e., in intervention research and current physical activity guidelines for children and youth) might increase enjoyment and adherence. The benefits of acute intermittent exercise (which simulates free-living activity) on postprandial lipaemia and microvascular function in inactive children with risk factors for cardiovascular disease should be investigated. Longitudinal investigations into the activity pattern of a much larger and more age-diverse sample of boys and girls are needed to determine whether any changes in aspects of the activity pattern might alter these and other health outcomes (i.e., cardiovascular risk factors).

Background: Competitive swimming is a sport that require high muscle strength to overcome the forces in the water. A phenomenon called post activation potentiation (PAP) is known to acutely increase power output. PAP can be defined as an increase in muscle performance after muscle contraction. Previous research on PAP has shown positive effects on different sports, including swimming. However, a limited amount of studies exists on PAP associated with swimming and distances longer than 100 meters. Aim: The aim of the study was to investigate if PAP for triceps brachii and latissimus dorsi with elastic bands can improve the aerobic performance, V4-speed, of elite freestyle swimmers. Methods: 13 elite swimmers participated in this study (mean ±SD: age 18 ±1.15). The participants performed three test sessions on two different days. The first occasion evaluated aerobic performance, V4-speed, where the participants performed a 400-m freestyle swim race and lactate and time were collected. At the second occasion, a 10-repetition maximum (RM) elastic resistance band test was done to get the right resistance band for each individual participant for the PAP exercise. At the third occasion, a PAP exercise, that mimics freestyle swim, with elastic resistance band was performed with 10 repetitions in two sets. After, a rest of six minutes was performed and then the same 400-m freestyle swim test as the first occasion. A paired samples t-test was used to evaluate significant differences between the swim test performed with and without a PAP exercise. Results: The study showed no statistical difference between the V4-speed with or without PAP exercise (p=0.93). An increase in lactate was seen after the PAP exercise (p=0.02). Conclusion: This study could not ensure an improvement of the aerobic performance, V4-speed, of elite swimmers when a PAP exercise, similar to a freestyle stroke, was performed before a 400-m submaximal freestyle swim race with elastic resistance band. Further research must be done in this area before coaches and athletes can apply this in training programs.

Bakgrund: Regelbunden fysisk aktivitet leder till positiva hälsoeffekter och är därmed viktig som primär- och sekundärprevention för flera olika sjukdomar och för tidig död. Primärprevention ges dock begränsat utrymme inom sjukvården och därmed kan ett samarbete med andra hälsofrämjande aktörer i samhället vara motiverat. Syfte: Att undersöka om deltagare skattar högre upplevd livskvalitet och fysisk aktivitetsnivå efter Friskis&amp;Svettis (F&amp;S) tio veckor långa ”Börja träna”-kurs samt undersöka om det fanns en korrelation mellan livskvalitet och fysisk aktivitetsnivå. Metod: 95 deltagare (81 kvinnor, 14 män) med en medelålder på 50 år fyllde i två enkäter, en före och en efter interventionen. En inomgruppsjämförelse samt en korrelationsanalys gällande livskvalitet och fysisk aktivitetsnivå gjordes. Resultat: Medianen för livskvalitet var 7 före interventionen och 8 efter vilket var en signifikant ökning (p=0,022). Även för fysisk aktivitet var ökningen signifikant med en median på 3 före interventionen och 4 efter (p&lt;0,001). I studien sågs ett mycket svagt samband mellan livskvalitet och fysisk aktivitetsnivå före interventionen (r=-0,172, p=0,122). Konklusion: Efter deltagande i F&amp;S ”Börja träna”-kurs skattade deltagarna högre livskvalitet och fysisk aktivitetsnivå. På grund av ett stort bortfall och flera metodologiska felkällor bör resultatet användas med försiktighet och vidare studier är därmed nödvändiga.

Aim Aerobic exercise may interfere with subsequent responses to strength training. The aim of this research was to examine the acute effects of cycling or running on subsequent leg strength performance. It was hypothesized that eccentric contractions induced by running would impair strength performance more than the cycling mode of exercise, which consist mainly of concentric muscle actions. Method In order to investigate if continuous running or cycling affected following strength performance, 6 healthy individuals (5 males, 1 female) were subjected to a randomized cross-over design. Subject characteristics were age (year) 25,5 ± 2,1, height (cm) 180,5 ± 6,4, and body weight (kg) 83 ± 3,4. The experimental sessions included three protocols: strength protocol (S) which included 3 repetitions measuring peak power followed by 3 sets to muscular failure at 80% of 1RM in the squat exercise; and continuous running (RS) and cycling (CS) conditions (40 minutes at 80% of maximal heart rate), followed by the S protocol. Peak power performance and total work volume was measured. Results Average peak power attained between the three protocols were CS = 1639± 444Watts (W), RS = 1633± 422 and S = 1565 ± 349. No significant differences were observed between the three conditions (P = 0,817). No differences across the three protocols was observed for highest peak power attained by each subject (P = 0,619). Total work volume performed (main effect P = 0,027) revealed a significant difference between CS = 2559 kg and S = 3715 kg (P=0,037), and CS and RS = 3345 kg (P=0,037) due to the lower loads lifted in CS.  Conclusions There were no differences observed between the three training protocols regarding peak power performance. When cycling exercise was performed prior to the strength session, the total volume lifted was lower than when performing the strength test alone. Thus, it is concluded that cycling exercise, but not running, interferes with subsequent strength training performance. / Syfte och frågeställningar Uthållighetsträning kan leda till försämrad styrkeprestation. Syftet med denna forskning var att undersöka de akuta effekterna från cykling eller löpning på efterföljande benstyrka. Hypotesen var att löpning, som omfattar excentriska muskelaktioner, skulle leda till en större försämring av efterföljande styrkeprestation jämfört med cyking, som främst omfattar koncentriska muskelaktioner. Metod För att undersöka om kontinuerlig cykling och löpning påverkade efterföljande benprestation, undersöktes 6 deltagare (5 män, 1 kvinna) i en randomiserad cross-over design. Försökspersonernas karakteristika var ålder (år) 25,5 ± 2,1, längd (cm) 180,5 ± 6,4, vikt (kg) 83 ± 3,4. Försökspersonerna utförde tre experimentella protokoll: styrka (S), vilket bestod av 3 repetitioner av maximal kraftutveckling efterföljt av 3 set till muskulär utmattning på 80% av 1RM i benböj; och löpning (RS) samt cykling (CS) protokoll (40-minuter på 80% av maximal hjärtfrekvens), efterföljt av S protokollet. Data för maximal kraftutveckling och total arbetsvolym samlades in.  Resultat Den genomsnittliga maximala effekten som uppnåddes mellan de tre protokollen var: CS = 1639 ± 444 Watt (W), RS = 1633 ± 422W och S = 1565 ± 349W. Inga signifikanta skillnader observerades mellan de tre förhållandena (P=0,817). Högst uppnådda effekten för varje deltagare mellan de tre förhållandena visade ingen skillnad (P=0,619). Totala arbetsvolymen (tidseffekt: P=0,027) visade signifikanta skillnader mellan CS = 2559 kg och S = 3715 kg (P=0,037), och CS och RS = 3345 kg (P=0,037) på grund av lägre vikt lyft vid CS. Slutsats Ingen skillnad observerades mellan de tre förhållandena angående maximal styrkeprestation. Den totala vikt volymen som kunde lyftas var dock lägre när cykling utfördes innan styrketestet. Slutsatsen är därför att cykling, men inte löpning, hindrar maximal träningsprestation vid ett efterföljande styrkepass.

Background Low aerobic fitness and obesity are associated with atherosclerosis, and thereforegreatly increase the risk of cardiovascular disease (CVD) and early death. It has long been known that atherosclerosis my begin early in life. Despite this fact, it remains unknown how obesity and aerobic fitness early in life influence the risks of atherosclerosis, CVD and death. Furthermore, it is unknown whether high aerobic fitness can compensate for the risks associated with obesity, and how genetic confounding affects the relationshipsof aerobic fitness with CVD and all-cause mortality. Thus, the main aims of this thesis were to investigate the associations of aerobic fitness in late adolescence with myocardial infarction (Study I), stroke (Study II) and all-cause mortality (Study III), and how genetic confounding influences the relationshipsof aerobic fitness with CVD, diabetes and death (Study IV). Methods The study population comprised up to1.3 million men who participated in mandatory Swedish military conscription. During conscription, all conscripts underwent highly standardized tests to assess aerobic fitness, body mass index, blood pressure and cognitive function. A physician also examined all conscripts. Data on subjects’ diagnoses, death and socioeconomic status during follow-up were retrieved using record linkage. Subjects were subsequently followed until the study endpoint, date of death or date of any outcome of interest. Associations between baseline variables and the risks of adverse outcomes were assessed using Cox’s proportional hazard models. Genetic confounding of the relationships between aerobic fitness and diabetes, CVD and death was assessed using a twin population and a paired logistic regression model. Results In Study I, low aerobic fitness at conscription was associated with an increased risk of myocardial infarction (MI) during follow-up (hazard ratio [HR] 0.82 per standard deviation increase). Similarly, in Study II, high aerobic fitness reduced the risk of stroke (HR 0.84 for ischemic stroke, HR 0.82 for hemorrhagic stroke; P &lt; 0.001 for all), and obesity was associated with an increased risk of stroke (HR 1.15 for ischemic stroke, HR 1.18 for hemorrhagic stroke; P &lt; 0.001 for all). In Study III, high aerobic fitness was also associated with reduced all-cause mortality later in life (HR 0.49, P &lt; 0.001). High aerobic fitness exerted the strongest protection against death from substance and alcohol abuse, suicide and trauma (HRs 0.20, 0.41 and 0.52, respectively; P &lt; 0.001 for all). Obese individuals with aerobic fitness were at higher risk of MI and all-cause mortality than were normal-weight individuals with low fitness (Studies I and III). In Study IV, fit twins had no reduced risk of CVD or death during follow-up compared with their unfit twin siblings (odds ratio 1.11, 95% confidence interval 0.88–1.40), regardless of how large the difference in fitness was. However, the fitter twins were protected against diabetes during follow-up. Conclusions Already early in life, aerobic fitness is a strong predictor of CVD and all-cause mortality later in life. In contrast to the “fat but fit” hypothesis, it seems that high aerobic fitness cannot fully compensate for the risks associated with obesity. The associationsof aerobic fitness with CVD and all-cause mortality appear to be mediated by genetic factors. Together, these findings have implications for the view of aerobic fitness as a causal risk factor for CVD and early death.

Dance has attracted little scientific interest on the effects of physical fitness improvements on performance and injury severity, particularly with respect to contemporary dance. The main aims of the current work were: a) to observe the physical demands of dance performance; b) to develop a reliable dance-specific performance tool; c) to assess the association between selected physical fitness parameters and performance in contemporary dance by using a new reliable method (AC test); d) to assess selected physical fitness parameters in relation to injury severity in contemporary dance; e) to study the effects of increased fitness parameters on performance through a randomized controlled trial. A total of 50 performances, performed by 20 dancers, were monitored by using a portable accelerometers (SWA armbands) and heart rate monitors while 45 performances in DVDs were video analysed. Six dancers and two dance teachers were recruited to test a newly developed performance tool. A sample made of 41 dancers were recruited and assessed for aerobic fitness (DAFT), lower body muscular power (jump height test), upper body muscular endurance (press-ups test), flexibility (active and passive hip ROM), body composition (skinfolds), performance (n=17) and injury severity (n=16). In order to investigate the effects of the supplementary fitness training on performance, 24 of the total 41 dancers, were randomly assigned to either an intervention (n=12) or control (n=12) group. The intervention group undertook a specifically designed exercise-training programme (circuit and WBV training) lasting six weeks. Both groups were re-tested for physical fitness levels and performance at the end of the intervention period. Results revealed that performance intensities varied from light to moderate while these were observed with the use of pliés and jumps as well as lifting other dancers. Based on the seven most frequently used criteria by selected pre-professional contemporary dance institutions and companies, a novel performance tool (AC tool) was developed with an inter-rater reliability of r=0.96. There was a significant correlation between aesthetic competence (AC) scores and jump ability (r=0.55) and press-ups (r=0.55), respectively. Stepwise backward multiple regression analysis revealed that the best predictor of AC was press-ups (R2=0.30, p=0.03, 95% confidence intervals=0.11–1.34). Univariate analyses also revealed that the interaction of press-ups and jump ability improved the prediction power of AC (R2=0.44, p=0.004, 95% confidence intervals=0.009–0.04). Pearson’s correlation coefficients detected significant negative correlations between the mean score recorded for injury severity (expressed as TDO) and lower body muscular power (r=-0.66; p=0.014); backward regression analysis also revealed that, from all studied parameters, the strongest predictor of TDO was lower body muscular power (p=0.014). For the intervention group repeated measures ANOVA revealed significant increases (pre vs. post) in aerobic fitness (p<0.05), lower body muscular power (p<0.05), upper body muscular endurance (p<0.05) and performance (p<0.05). Linear regression analyses indicated that the only significant predictor of AC was aerobic capacity (F=7.641; p=0.03); the interaction of press-ups and aerobic capacity (F=6.297; p=0.036), and lower body muscular power with aerobic capacity (F=5.543; p=0.05) demonstrated an improved prediction power. These results show that the observed contemporary dance performance is an intermittent type of activity of moderate intensity. Given the reliability of the AC tool, it is concluded that upper body muscular endurance and jump ability best predict AC of contemporary dancers. Reduced lower body muscular power is associated with increased severity of injuries. Finally, supplementary exercise training significantly increases lower body muscular power, upper body muscular endurance and aerobic fitness, which in turn are beneficial to improve AC of contemporary dancers.

This investigation examined the effects of aerobic fitness and the Type A behavior pattern on cognitive functioning in the split-attention (dual task) paradigm. Sixty-four adults were classified as Type A or B by means of the Jenkins Activity Survey, and as Runner or Sedentary using self-reports of physical activity. Under challenging instructions, subjects performed a primary task (Raven Advanced Progressive Matrices) and secondary task (Backward Digit Span) alternatively under single and dual task conditions. There was a significant interaction between aerobic fitness and task condition such that Runners outperformed Sedentary subjects under dual, but not single, task conditions on the secondary task. No differences were found on the primary task. Backward Digit Span performance under dual, but not single, task conditions, was also found to be positively related to the subjects eating a low cholesterol diet and maintaining a healthy weight. Contrary to predictions, there were no significant effects of the Type A behavior pattern, either main or interaction, on any of the cognitive measures. Type A Runners exceeded Type B Runners in aerobic points, races per year, runs per week, Personal Record attempts, and level of dissatisfaction with performance. There were no differences in the tendency to run while injured, use of a stopwatch during training, or effort exerted in races. Overall, these findings suggest that an ability to perform under split-attention (dual task) conditions is positively related to aerobic fitness, a low-fat diet, and maintenance of a healthy weight. In addition, Type A Runners differ from B Runners in some, but not all, aspects related to the Type A pattern, suggesting that aerobic exercise may modify to a limited extent the Type A behavior pattern. The failure to find A-B differences in attentional style consistent with prior research (Matthews & Brunson, 1979) or interaction of type and exercise may reflect the nature of the sample and tasks in this particular investigation, compared with previous studies.

Thirty-one college age females enrolled in aerobic dance conditioning classes were subjects. The purposes were to determine if aerobic dance is sufficiently vigorous to elicit a heart rate capable of producing a training effect and to determine whether a training effect heart rate level can be maintained. The narco-biosystems telemetry was used to monitor heart rates. Each subject performed one aerobic dance at three trials. Twelve-minute run/walk pretests and post-tests were given to assign fitness levels. Results of the study indicate that aerobic dance is an effective cardiovascular training program. Resting heart rates decreased, fitness levels improved, and training intensity heart rates were elicited and maintained at each of the trials.