Tyrimo objektas – irkluotojų aerobinis pajėgumas. P. Karoblio (2003) teigimu talentingų sportininkų paieška, jų atranka ir sportinis rengimas – viena svarbiausių šiuolaikinio sporto problemų. Svarbiausia yra sudaryti palankias sąlygas siekti aukštų sportinių pasiekimų, todėl turėtų būti tinkamai projektuota sportininkų rengimo sistema: treniruočių metodika, organizavimas, kontrolė ir valdymas. Irklavime varžomasi klasikinėje 2000m distancijoje. Distancijos įveikimo trukmė nuo 5 min. 20 s iki 9 min, priklausomai nuo valčių klasės, meistriškumo ir nuo oro sąlygų. Irklavime sportinius rezultatus sąlygoja sportininkų fizinio ir funkcinio pajėgumo lygmuo. Funkcines irkluotojų galimybes ir jų realizavimą lemia daugelis jų veiksnių: organizmo aerobiniai ir anaerobiniai gebėjimai, techninis ir taktinis bei psichologinis parengtumas (Skernevičius, 1997). Kintant socialinėms, ekonominėms sąlygoms, plėtojant sportą, didėjant konkurencijai iškyla problema, kaip tobulinti Lietuvos didelio meistriškumo irkluotojų rengimą, kad jų meistriškumas pasiektų tarptautinį lygį, leistų iškovoti medalius svarbiausiose varžybose, dėl to svarbu stebėti sportininkus, atliekant fiziologinius testavimus. Tačiau mažai analizuotas Lietuvos irkluotojų rengimas metiniu ciklu, kurie ruošiasi olimpinėms žaidynėms: apie jų treniruočių fizinius krūvius, organizmo fizinių ir funkcinių galių kaitą ir raidą nėra daug informacijos. Kadangi Lietuvoje irkluotojams mažai atliekami fiziologiniai testavimai, siekiant... [toliau žr. visą tekstą] / Research object – rowers‘ aerobic capacity. P. Karoblis (2003) according to the talented athletes in the selection and preparation of sports one of the most important problems of modern sport. The key is to facilitate the achievement of high sports achievements and should be properly designed by athletes training system: training methods, organization, control and management. Rowing competed classic 2000 m distance. Superable time of distance is 5 minutes 20 seconds to 9 minutes depending on boat class, craftsmanship and the weather. Rowing sports performance athletes causes physical and functional capacity level. Rowers functional capabilities and their realization is determined by many factors: the body's aerobic and anaerobic capacity, technical and tactical and psychological maturity (Skernevičius, 1997). Changing social, economic conditions for the development of the sport increasing competition there is a problem how to improve the elite rowers of Lithuanian preparing, their mastery of reach international level, would win medals in major competitions conditions, it is important to monitor athletes during physiological stress. However, Lithuania rowers are few analyzed preparing the annual cycle of preparing for the Olympics: their physical training load, the organism physical and functional abilities change and evolution is not a lot of information. Since Lithuania rowers made few physiological stress to control and monitor the fitness of athletes, we believe, that this... [to full text]

14 pregnant women were investigated of the age of 24-33 (on the 26th pregnancy week) and 12 not pregnant women of the age of 24-33. Women who were investigated were divided into 3 groups: the first group consisted of 7 pregnant women who did exercises in the water for 60 minutes 3 times a week; the second group – 7 pregnant women who didn’t do exercises in the water; and the third group – 12 not pregnant women who didn’t do exercises. All the three groups did load of the same physical intensity which was gradually increased with using veloergometre “ Monak 834 E Ergomedic”, with mask of gas analyzer “ Oxycon Mobile” which ascertained spiroergometrical index ( lung ventilation, oxygen uptake, breath volume, breath rate, the maximum oxygen pulse, coefficient of respiration) and the pulsometre “ Polar Accurex- Puls”, which registered heart rate. After the load in the 1th and 2th groups of pregnant women the foetus heart rate was registered by the electronic stethoscope. The results of our investigation showed that gymnastic exercises have a positive effect upon the aerobic capacity of pregnant women. The length of child – birth is shorter of pregnant women who do exercises and also complications is less than of not exercised pregnant women. All the women who were investigated gave birth to healthy new born babies; however the weight of new born babies of pregnant women who did exercises was smaller.

Salinity and oxygen availability have long been recognised as important factors influencing animal physiology and therefore species distribution. The maintenance of appropriate cellular ion levels is critical for many essential physiological processes, but at the same time is energetically expensive. Since hypoxia is likely to impose aerobic limitations for ATP generation, the maintenance of salt and water homeostasis could be at risk during hypoxia. The amphidromous inanga (Galaxias maculatus) is well known for its salinity tolerance and its life cycle that involves several salinity related migrations. During these migrations inanga also frequently encounters hypoxic waters, and therefore must maintain energy homeostasis when aerobic metabolism may be compromised. The present study has investigated behavioural, physiological, biochemical and molecular mechanisms by which inanga tolerate changes in salinity and hypoxia. After 14 days of acclimation to salinities ranging from freshwater to 43‰, inanga showed physiological acclimation. This was evident by no changes in metabolic rates or energy expenditures through this salinity range. Energy balance seemed to be tightly and efficiently controlled by changes in the proportion of protein and lipids used as energy substrate. No mortalities and only minor changes in plasma osmolality also indicated salinity acclimation. The remarkable osmoregulatory capacity of inanga was also evidenced after a seawater challenge. The osmotic balance of inanga was only disrupted during the first 24 hours after the challenge, evidenced by an increase in plasma osmolality and plasma Na+, and a decrease in muscle water content. These physiological changes were correlated with changes at the molecular level. Different isoforms of the catalytic subunit of the Na+,K+-ATPase (NKA) were isolated, partially sequenced and identified in inanga. Phylogenetic analysis grouped inanga isoforms (α-1a, α-1b, α-1c) with their respective homologues from salmonids. Patterns of mRNA expression were also similar to salmonids, with α-1a being downregulated and α-1b being up-regulated following seawater challenge. Previous to this study, NKA isoform switching was reported to occur only in salmonids and cichlids. The presence of NKA subunits that change with environmnetal salinity in inanga indicates that this isoform switching phenomenon is much more widespread among teleost lineages than previously thought. Aiming to elucidate the hypoxia tolerance of inanga, oxygen consumption rate as a function of decreasing external PO2 was evaluated. At no point did inanga regulate oxygen consumption, suggesting that this species is an oxyconformer. This is the first robust demonstration of the existence of oxyconforming in fish. Evaluation of the scaling relationship between oxygen consumption and fish size in normoxia, showed that the exponent of this relationship fell within the range previously reported for fish. However, in hypoxic conditions the scaling relationship was less clear suggesting different size-related mechanisms for tolerating hypoxia. Analysis of the aerobic and anaerobic metabolism of small and large fish, showed that smaller inanga were able to sustain aerobic metabolism for longer than larger inanga, which instead relied on anaerobic metabolism for extending their survival. This knowledge is likely to be of value for the conservation of this iconic fish species, by incorporating these size related differences in hypoxia tolerance in streams management. In light of the unusual oxyconforming response of inanga, a study examining the behavioural responses of this species to declining dissolved oxygen was performed. Inanga did not display a behaviour that might reduce energy expenditure during oxygen limitation; instead swimming activity and speed were elevated relative to normoxia. As hypoxia deepened inanga leaped out of the water, emersing themselves on a floating platform. Once emersed, fish exhibited an enhanced oxygen consumption rate compared to fish that remained in hypoxic water. Although this emersion behaviour was hypothesised to be of physiological advantage, both aquatic hypoxia and emersion resulted in similar physiological and biochemical consequences in inanga. While in hypoxic water oxygen availability seemed to be the limiting factor, in air failure of the circulatory system was hypothesised to be the cause of a similar metabolic signature to that found in aquatic hypoxia. Overall, inanga seemed to be not particularly well adapted to tolerate aquatic hypoxia. In light of the increasing likelihood of anthropogenic-induced hypoxia in inanga habitats, this is likely to have negative consequences for the future of inanga populations in the wild. Although this study provides the mechanisms behind the exceptional salinity tolerance of inanga, its susceptibility to hypoxia is likely to impose further constraints for the osmoregulatory processes that guarantee inanga survival during life cycle migrations. The results of the present study are relevant for understanding and managing the fishery of this economically- and culturally important fish species.

The purpose of this study was to determine the effect of a light-moderate versus hard exercise intensity on health and fitness benefits in a previously sedentary population. Twenty-six subjects, 17 male (mean age 45 + 3 yrs), 9 female (mean age 48 + 3 yrs) with at least one coronary artery disease risk factor volunteered to participate in this study. Subjects underwent laboratory testing comprising of, resting heart rate and blood pressure, body composition, blood lipid analysis and aerobic capacity (V02 ), prior to and 22-32 weeks after participating > 2 days per week in the Adult Physical Fitness Program (APFP) at Ball State University. After an initial exercise prescription subjects self selected an exercise intensity between 40-80% of their maximal heart rate range (MHRR) at which to train. Subjects were then grouped into those who trained at < 60% (light-moderate) and those who trained at > 60% (hard) of their MHRR.Those that self selected a hard training intensity did show a significantly greater decrease in diastolic blood pressure than the light-moderate intensity group. Subjects received a main training effect with a mean decrease in systolic blood pressure (123 ± 2.8 to 119 ± 2.4 mmHg), diastolic blood pressure (78 ± 2.2 to 75 ± 1.7 mmHg), and mean increases for HDL-cholesterol (49 ± 2.5 to 53 ± 2.8 mg/dL), absolute functional capacity (2.676 +.162 to 2.843 +.169 L/min) and relative functional capacity (30.2 ± 1.5 to 32.8 + 1.8 ml/kg/min). In conclusion this study demonstrated health and fitness benefits when training at least 2 days per week with greater effects when training at a hard versus light-moderate intensity with regards to diastolic blood pressure. / School of Physical Education

The purpose of this study was to evaluate the intermodal reliability of perceptually-based exercise intensity among four machines: Treadmill (TM), Stationary cycle (CB), Body Trec elliptical arm/leg (BT), and AirDyne (AD). Nineteen subjects (8 male and 11 female; age 44 + 12 yrs) completed one GXT on each of the machines, following a mode-specific protocol. Subjects also completed two 15 minute production trials (PTs) on each machine at self-selected workrates corresponding to target RPEs of 11-12 (L) and 15-16 (H). In the PTs, workloads were self-adjusted through the first 5 minutes and then remained stable for the rest of the trial. Modes were randomly assigned, and subjects were blinded to the workload throughout each trial. Heart rate (HR) and oxygen uptake (V02) were obtained during the final 5 min. of each trial using a Polar HR monitor and Aerosport TEEM 100. Also, blood lactate (BLC) was sampled immediately following exercise at each intensity. Intermodal reliability was assessed using ANOVA, intraclass correlations (R), coefficients of variation (CV), and mean absolute differences for HR, V02, and BLC during the second PT. ANOVA revealed nointeraction for BLC at either the LOW or HIGH. Post -hoc analysis showed the TM and/or BT to produce significantly higher physiological responses at both intensity levels. At the L and H, intermodal Rs were: HR (.84/.88), VO2 (8/.77) and BLC (0.09/0.67). Significant intrasubject differences were observed at the L for HR (11-47bpm, VO2 (.04-1.46 L/min), and BLC (.29-12.94 mM/L). The H trials followed a very similar trend. Using a HR criteria of +2 beats/15 sec. to assess intrasubject reliability, 0% of the subjects were reliable at both the L and H. This data suggests that perceptually-based exercise across multiple modes is associated with significant intraindividual variability, and reliability is dependent upon the statistical design and physiological variable being used. In conclusion, it is recommended that extensive exercise testing be performed to ensure that individual participants can reliably use the RPE scale, prior to using an RPE value to prescribe the intensity of exercise. / School of Physical Education

Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science

Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science

Despite pharmacological advances, exercise remains a cost effective preventative for cardiovascular disease (CVD) by acutely and chronically lowering systolic blood pressure (SBP). Although numerous studies have investigated aerobic and resistance training’s role in eliciting an acute SBP response termed post-exercise hypotension (PEH), few researchers have investigated how performing both cardiovascular and weight training in a single session (concurrent training) or how different prescriptions for order of exercise modality will elicit this PEH response; no known studies have attempted altering the order of exercise types within each session. This study seeks to determine if the order of exercise type will affect a PEH response following concurrent exercise. Participants (n=13), considered low risk for cardiovascular disease participated in a control session, graded exercise test (GXT) and two concurrent sessions, with concurrent sessions counterbalanced for order of exercise mode. Recovery SBP was analyzed in the laboratory for sixty minutes and for twenty-four hours thereafter using an ambulatory blood pressure monitor. All exercise conditions elicited a depression in SBP; however, only the cardiovascular-weight training (CVWT) concurrent session elicited PEH (p = 0.05). However, there were no differences in SBP attenuation between conditions. There was no main effect for PEH between conditions during twenty-four hour assessment. With no statistically significant differences in the magnitude of PEH twenty-four hours after exercise, it may be determined that the order of exercise does not vi affect the preventative attributes of aerobic and resistance exercise in regards to acute SBP response. Furthermore, only exercise involving resistance training (CVWT) provoked PEH during the first 60 minutes; therefore it may be argued that individuals should pair cardiovascular exercise with weight training in order to elicit the greatest cardiovascular benefits. Future studies should consider evaluating the effect of time of day and PEH following concurrent exercise to determine if pairing exercise modalities will at different times will affect the blood pressure response.

Prevention and treatment of type 2 diabetes mellitus (T2DM), relies heavily on self-care behaviours such as dietary modification, physical activity, and medication adherence. Ability to perform these self-care behaviours depends, at least in part, on executive function (EF). Recent evidence suggests a correlation between T2DM and impaired cognitive function, including EF. Given the importance of EF for regulation of behaviours, and the importance of self-care in diabetes management, attenuated EF would represent a potential barrier to proper disease management. Thus the objective of Study 1 was to examine the association between T2DM and EF through meta-analytic techniques. Medline, PsychoInfo, and Scopus, as well as article references, were used to identify studies comparing individuals with T2DM to a control population. Effect size was calculated using cohen’s d and random effects modeling, and the potential impact of moderators (age, sex, and T2DM duration) were examined. Review of 60 studies (59 articles), revealed a significant, small-to-moderate effect size (d=-0.249, p<0.001) such that those with T2DM have lower EF. This finding was consistent across all aspects of EF examined (verbal fluency, mental flexibility, inhibition, working memory, and attention), and the association was stronger for those with shorter disease duration. The findings of study 1 illustrate that although individuals with T2DM have a great need for EF, as evidenced by the reliance of self-care behaviours on EF, this population has lower EF upon which to draw to perform these behaviours. Thus, strategies that improve EF, such as aerobic exercise, may be particularly relevant to this population. Acute aerobic exercise has been shown to improve EF in young and older adults; however this effect had not yet been examined in individuals with T2DM. Thus the objective of Study 2 was to examine the effects of acute aerobic exercise on EF in adults with T2DM. A within-subject design was used to compare the change in EF task performance following moderate and minimal intensity aerobic exercise, using Stroop and GNG to measure EF. Analysis revealed a significant effect of moderate exercise in women (but not men) and recently active (but not inactive) individuals, such that moderate exercise mitigated the self-regulatory fatigue effect observed following exercise. This study provides preliminary evidence of a significant beneficial effect of moderate aerobic exercise on EF in female and recently active adults with T2DM.

Reaction water, a high-strength COD (chemical oxygen demand) petrochemical effluent, is generated during the Fischer-Tropsch reaction in the SASOL Synthol process at SASOL SynFuels, Secunda, South Africa. Distillation of the reaction water to remove non- and oxygenated hydrocarbons yields approximately 25 - 30 ML/d of an organic (carboxylic) acid-enriched stream (average COD of 16 000 mg/L) containing primarily C2 – C5 organic acids, light oils, aldehydes, ketones, cresols and phenols. Together with the Oily sewer water (API) and Stripped Gas Liquor (SGL) process streams, this process effluent is currently treated in ten dedicated activated sludge basins. However, the successful operation of these activated sludge systems has proven to be difficult with low organic loading rates (3.5 kg COD/m3.d) low COD removal efficiencies (<80 %) and high specific air requirements (60 - 75 m3 air/kg CODrem). It is hypothesised that these operational difficulties can be attributed to organic shock loadings, variation in volumetric and hydraulic loadings, as well as variations in the composition of the various process streams being treated. Due to the fact that the Fischer-Tropsch (Synthol) reaction water constitutes 70 % of the COD load on the activated sludge systems, alternative processes to improve the treatment cost and efficiency of the Fischer-Tropsch acid stream are being investigated. Various studies evaluating the aerobic and anaerobic treatment of Fischer-Tropsch reaction water alone in suspended growth wastewater treatment systems have proven unsuccessful. High rate fixed-film processes or biofilm reactors, of which the fluidised-bed reactors are considered to he one of the most effective and promising processes for the treatment of high-strength industrial wastewaters, could he a suitable alternative. The primary aim of this study was to evaluate the suitability of biological fluidised-bed reactors (BFBRs) for the treatment of Fischer-Tropsch reaction water. During this study, the use of aerobic and anaerobic biological fluidised-bed reactors (BFBR), using sand and granular activated carbon (GAC) as support matrices, were evaluated for the treatment of a synthetic effluent analogous to the Fischer-Tropsch reaction water stream. After inoculation, the reactors were operated in batch mode for 10 days at a bed height expansion of 30% and a temperature of 30 ºC to facilitate biofilm formation on the various support matrices. This was followed by continuous operation of the reactors at hydraulic retention times (HRTs) of 2 days. While the COD of the influent and subsequent organic loading rate (OLR) was incrementally increased from 1 600 mg/L to a maximum of 20 000 mg/L and 18 000 mg/L for the aerobic and anaerobic reactors, respectively. Once the maximum influent COD concentration had been achieved the OLR was further increased by decreasing the HRTs of the aerobic and anaerobic reactors to 24h and 8h, and 36h, 24h and 19h, respectively. The dissolved O2 concentration in the main reactor columns of the aerobic reactors was constantly maintained at 0.50 mg/L. Chemical Oxygen Demand (COD) removal efficiencies in excess of 80 % at OLR of up to 30 kg COD/m3.d were achieved in the aerobic BFBRs using both sand and GAC as support matrices. Specific air requirements were calculated to be approximately 35 and 41 m3 air/kg CODrem for the BFBRs using sand and GAC as support matrices, respectively. The oxygen transfer efficiency was calculated to be approximately 5.4 %. At high OLR (> 15 kg COD/m3.d) significant problems were experienced with plugging and subsequent channelling in the BFBR using GAC as support matrix and the reactor had to be backwashed frequently in order to remove excess biomass. Despite these backwash procedures, COD removal efficiencies recovered to previous levels within 24 hours. In contrast, no significant problems were encountered with plug formation and channelling in the BFBR using sand as support matrix. In general the overall reactor performance and COD removal efficiency of the aerobic BFBR using sand as support matrix was more stable and consistent than the BFBR using GAC as support matrix. This BFBR was also more resilient to variations in operational conditions, such as the lowering of the hydraulic retention times and changes in the influent pH. Both aerobic reactors displayed high resilience and COD removal efficiencies in excess of 80 % were achieved during shock loadings. However, both reactors were highly sensitive to changes in pH and any decrease in pH below the pKa values of the volatile fatty acids in the influent (pKa of acetic acid = 4.76) resulted in significant reductions in COD removal efficiencies. Maintenance of reactor pH above 5.0 was thus an essential facet of reactor operation. It has been reported that the VFA/alkalinity ratio can be used to assess the stability of biological reactors. The VFA/alkalinity ratios of the aerobic BFBRs containing sand and GAC as support matrices were stable (VFNalkalinity ratios of < 0.3 - 0.4) until the OLR increased above 10 kg/m3.d. At OLRs higher than 10 kg/m3.d the VFA/alkalinity ratios in the BFBR using sand support matrix increased to 4, above the failure limit value of 0.3 - 0.4. In contrast the VFA/alkalinity ratios of the BFBR using GAC support matrix remained stable until an OLR of 15 kg/m3.d was obtained, where the VFA/alkalinity ratios then increased to > 3. Towards the end of the study when an OLR of approximately 25 kg/m3.d was obtained the VFA/alkalinity ratios of both the BFBRs using sand and GAC as support matrices increased to 9 and 6 respectively, indicating the decrease in reactor stability and acidification of the process. Total solid (TS) and volatile solid (VS) concentrations in the aerobic BFBRs were initially high and decreased over time. While the total suspended solids (TSS) and volatile suspended solids (VSS) concentrations were initially low and increased over time as the OLR was increased, this is thought to be as a result of decreased HRT leading to biomass washout. The anaerobic BFBR using sand as support matrix never stabilised and COD removal efficiency remained very low (< 30 %), possibly due to the high levels of shear forces. Further studies concerning the use of sand as support matrix were subsequently terminated. An average COD removal efficiency of approximately 60 % was achieved in the anaerobic BFBR using GAC as a support matrix at organic loading rates lower than 10 kg COD/m3.d. The removal efficiency gradually decreased to 50 % as organic loading rates were increased to 20 kg COD/m3.d. At OLRs of 20 kg COD/m3.d, the biogas and methane yields of the anaerobic BFBR using GAC as support matrix were determined to be approximately 0.38 m3 biogas/kg CODrem (0.3 m3 biogas/m3reactor vol.d), and 0.20 m3 CH4/kg CODrem (0.23 m3 CH4/m3reactor vol.d), respectively. This value is 57 % of the theoretical maximum methane yield attainable (3.5 m3 CH4/kg CODrem). The methane yield increased as the OLR increased, however, when the OLR reached 8 kg/m3.d the methane yield levelled off and remained constant at approximately 2 m3 CH4/m3reactor vol.d. Although the methane content of the biogas was initially very low (< 30 %), the methane content gradually increased to 60 % at OLRs of 20 kg COD/m3.d. The anaerobic BFBR using GAC as support matrix determined that as the OLR increased (>12 kg/m3.d), the VFA/alkalinity ratio increased to approximately 5, this is indicative of the decrease in stability and acidification of the process. The anaerobic BFBR using GAC as support matrix experienced no problems with plug formation and channelling. This is due to the lower biomass production by anaerobic microorganisms than in the aerobic reactors. The TS and VS concentrations were lower than the aerobic concentrations but followed the same trend of decreasing over time, while the TSS and VSS concentrations increased due to decreased HRTs. The anaerobic BFBR was sensitive to dramatic variations in organic loading rates, pH and COD removal efficiencies decreased significantly after any shock loadings. Compared to the activated sludge systems currently being used for the biological treatment of Fischer-Tropsch reaction water at SASOL SynFuels, Secunda, South Africa, a seven-fold increase in OLR and a 55 % reduction in the specific air requirement was achieved using the aerobic BFBRs. The methane produced could also be used as an alternative source of energy. It is, however, evident that the support matrix has a significant influence on reactor performance. Excellent results were achieved using sand and GAC as support matrices in the aerobic and anaerobic BFBRs, respectively. It is thus recommended that future research be conducted on the optimisation of the use of aerobic and anaerobic BFBRs using these support matrices. Based on the results obtained from this study, it can be concluded that both aerobic and anaerobic treatment of a synthetic effluent analogous to the Fischer-Tropsch reaction water as generated by SASOL in the Fischer-Tropsch Synthol process were successful and that the application of fluidised-bed reactors (attached growth systems) could serve as a feasible alternative technology when compared to the current activated sludge treatment systems (suspended growth) currently used. Keywords: aerobic treatment, anaerobic treatment, biological fluidised-bed reactors, petrochemical effluent, Fischer-Tropsch reaction water, industrial wastewater. / Thesis (M. Omgewingswetenskappe)--North-West University, Potchefstroom Campus, 2004.