Overexpression of the enzyme iNOS induces apoptotic cellular death by increasing indices of pro-inflammation and oxidative stress. Aerobic physical activity has been known to have anti- inflammatory benefits and reduce oxidative stress. Purpose: Therefore, this study aimed to examine the impact of aerobic fitness on LPS-induced iNOS mRNA expression and the relationship of this expression with indices of oxidative stress, pro-inflammation and apoptosis in isolated leukocytes. Methods: Whole blood samples from aerobically fit and unfit males were stimulated with and without LPS. Thereafter, iNOS mRNA expression and MDA, TNF-α and p53 concentrations were analyzed. Results: iNOS mRNA expression levels following LPS stimulation were not increased in both groups, and correlational analyses were not consistent with mechanistic predictions. Discussion: Numerous factors including timing of sample quantification, the high level of health of the subject population, and alternative intracellular mechanisms impacting biomarkers analyzed, may have influenced leukocyte iNOS mRNA expression levels.

For decades strength and conditioning professionals have been seeking optimal training volumes and intensities to yield maximum performance outcomes without the onset of injury. Unfortunately, current studies apply experimental training techniques without considering the individuals’ response to the imposed training load. Due to the vast genetic variability and extraneous environmental factors that affect one’s ability to recover, results from such studies are controversial and inconclusive. Athlete monitoring systems offer an objective assessment that is purported to evaluate an individual’s physiological readiness to adapt to an overload stimulus and thus allow for daily manipulations in training loads (i.e., fluid periodization). However, little is known about the efficacy of this technology to enhance training outcomes. Therefore, the purpose of this study was to examine the effect of fluid periodization on performance outcomes in American football players. Sixty-one Division 1 collegiate American football players (Age: 19.7 ± 0.9 yr; Height: 1.88 ± 0.3 m; Mass: 107.3 ± 11.1 kg) participated in this study and were stratified into experimental (n=33) and control (n=28) groups. Performance outcomes were measured prior to and following the summer training program. Physiological readiness parameters (heart rate variability and direct current brain wave potential outcomes) were measured daily in the experimental group only with Omegawave technology prior to training sessions and adjustments in training volumes or intensity were made based upon physiological readiness outcomes. The control group trained according to the daily prescribed workout. The findings from this study indicate that the experimental group significantly improved in vertical jump, vertical power, aerobic efficiency and broad jump (P < 0.01) compared to the control group. Additionally, significant improvements and effect sizes between groups were noted for fat-free mass (relative improvement: 54%, effect size: 0.30), vertical jump (relative improvement: 157%, effect size: 1.02), vertical power (relative improvement: 94%, effect size: 0.86), broad jump (relative improvement: effect size: 592%, 0.81), triple broad jump (relative improvement: 338%, effect size: 0.63), aerobic efficiency (relative improvement: 154%, effect size: 1.02), and medicine ball overhead throw (relative improvement: 50%, effect size: 0.26). In addition, the experimental group achieved these improvements with less core (-9.5%) and accessory (-13.2%) training volume (P < 0.01). In conclusion, fluid periodization produced greater improvements in performance outcomes at a reduced training load compared to a similar unmodified periodization scheme. These findings highlight the importance of modifying training parameters based upon the daily physiological state of the athlete.

Water polo is a highly dynamic and physically demanding sport that has heretofore not inspired nearly as much research as other overhead sports such as baseball or swimming. As in almost all overhead sports, water polo puts its players at high risks for shoulder injuries since the motions required to perform the sport at an optimum level push the limits of normal shoulder function. Human shoulders are inherently unstable as a tradeoff to their flexibility. Because of this instability, many structures are required to work concurrently to keep the shoulder in place. These structures include muscles, ligaments and cartilages. It is important to recognize that the shoulder is not a singular joint in itself but rather a highly mobile complex that can perform many nuanced motions. Shoulder instability can cause a variety of injuries such as impingement, which occurs often among overhead athletes. This malady refers to a pathologic limitation of normal subacromial space that causes structures to be in abnormal contact with each other, which causes abrasive and pinching forces. These forces can result in a range of shoulder maladies including bursitis, tendinitis, and tearing of muscles and ligaments. Impingement is very apparent in both swimmers and water polo players due to the repetitive stresses present in each sport. In swimmers, impingement has been relatively well researched; the freestyle stroke utilized in water polo, however, is fundamentally different in that water polo players keep their heads and chests erect out of the water with a stroke known as head-up freestyle. Hitherto unknown are the biomechanics of this stroke and the extent to which impingement in water polo players is caused and/or worsened by this form of freestyle. The proposed research is a two-part study to investigate the biomechanics of water polo head-up freestyle as a first step to understanding its role in impingement in water polo players. First, experienced water polo players with healthy shoulders approved by the IRB committee of Scripps College will be recruited in this study, and their head-up freestyle kinematic sequences and muscle activities will be recorded by synchronized high-speed cinematography and fine-wire electromyography. These data will be compared to those of head-down freestyle in the literature to understand the biomechanical differences between head-up in and head-down. Part II of the study will recruit experienced water polo players with existing shoulder impingement in addition to those with healthy shoulders in Part I, and their head-up freestyle will be recorded in the same manner. These data will be compared to those in Part I to understand how the head-up stroke differs between impinged and healthy shoulders. This research will provide a basis for the understanding of impingement in head-up freestyle to ultimately increase the safety of the players. Further studies should be conducted to compare the patterns of biomechanical differences between healthy and impinged shoulders in head-up vs. head-down, analyze impingement in each phase of the head-up swim stroke, and investigate how the rate of impingement is altered by fatigue and poor technique.

This thesis aimed to develop a running heat tolerance test (RHTT) to assess changes in heat tolerance and to investigate the mechanism and optimisation of heat acclimation (HA) for female athletes. The first study introduced a RHTT and assessed its repeatability. Results demonstrate good agreement, strong correlations and small differences between repeated trials. The typical error of measure values suggested low within-participant variability. Furthermore, the RHTT was effective in differentiating between individuals’ physiological responses, demonstrating that heat tolerance lies along a continuum. The second study examined the sensitivity of the RHTT to changes in heat tolerance and to evaluate individual responses to HA. Results demonstrate that the RHTT is sensitive to changes in heat tolerance and that the magnitude of adaptation is highly individual; supporting the use of the RHTT in future investigations. Reducing thermal strain through HA in not fully understood for a female population. The third study compared males’ and females’ temporal patterning to short-term HA (STHA; 5-d) and long-term HA (LTHA; 10-d). The RHTT was used to quantify changes in heat tolerance. The results confirm that whilst STHA may be effective in achieving partial adaptation in males and females, females require LTHA to establish reductions in thermoregulatory and cardiovascular strain. Improved thermotolerance following HA, reduces disruptions to cellular homeostasis principally, but not exclusively, by increasing basal heat shock protein 72 following transcription of its gene (Hsp 72 mRNA) as part of the heat shock response (HSR). The fourth study compared males’ and females’ Hsp72 mRNA response during STHA and LTHA. The similar transcription of Hsp72 mRNA observed in all participants suggests that there are no differences in the endogenous criteria to elicit the HSR between sexes. The fifth study assessed the effectiveness of preceding STHA with a passive heat exposure (HAsauna) in females. HAsauna resulted in reductions in thermoregulatory, cardiovascular and perceptual strain. The adaptation pathway was likely mediated in part, by plasma volume expansion and an improved thermoeffector and thermosensitivity response of the sudomotor function. Together, evidence in this thesis supports the notion that special considerations need to be taken when using HA to attenuate thermoregulatory strain in female athletes prior to training and competing in the heat.

Submaximal exercise performance is, in part, limited by the accumulation of metabolic byproducts and energy system capacities. Curcumin and the combination of curcumin and fenugreek soluble fiber (CurQfen®) have been shown to increase endogenous antioxidants and metabolic byproduct clearance as well as reduce inflammation and lipid peroxidation, and therefore, may enhance submaximal aerobic thresholds. In addition, there is evidence that the galactomannan component of fenugreek, used to enhance bioavailability of curcumin, may also have potential physiological effects related to the up regulation of free fatty acid oxidation Therefore, the purpose of this study was to examine the effects of curcumin and fenugreek soluble fiber supplementation on the ventilatory threshold (VT), respiratory compensation point (RCP), maximal oxygen consumption (O2 peak), and time to exhaustion (Tlim)derived from a graded exercise test (GXT). Forty-five untrained, college-aged, male (n = 24) and female (n = 21) subjects (mean age ± SD: 21.2 ± 2.5 yr) were randomly assigned to one of three supplementation groups; placebo (PLA, n=13), 500 mg·day-1 CurQfen® (CUR, n=14), or 300 mg·day-1 fenugreek soluble fiber (FEN, n=18). All of the subjects completed a maximal GXT on a cycle ergometer to determine the VT, RCP, O2 peak, and Tlim before (PRE) and after (POST) 28 days of daily supplementation. The VT and RCP were determined from the V-slope method for the ventilation (E)vs. O2 and E vs. CO2, respectively. Separate, one-way ANCOVAs were used to examine the between group differences for adjusted POST VT, RCP, O2 peak, and Tlim values, with the respective PRE test value as the covariate. The adjusted POST VT-O2 for the CUR (mean ± SD= 1.593 ± 0.157 L·min-1) and FEN (1.597 ± 0.157L·min-1) groups were greater than (p= 0.04 and p= 0.03, respectively) the PLA (1.465 ± 0.155L·min-1) group, but the FEN and CUR groups were not different (p = 0.94). The one-way ANCOVAs for RCP (F = 3.177, p = 0.052), O2 peak (F = 0.613, p = 0.547), and Tlim (F = 0.654, p = 0.525) indicated there were no significant differences among groups. These findings suggested that CurQfen® and/or fenugreek soluble fiber may improve submaximal, but not maximal, aerobic performance indices in untrained subjects.

The purpose of the study was to examine the effects of a school-based cross-training program on body mass index (BMI), attitudes toward physical activity (ATPA), and physical activity (PA) levels of children in the 4th and 5th grades. Children (N = 118) were divided into control (n = 60) and experimental (n = 58) groups based on class availability. While the control group continued academic classes as usual, the experimental group participated in cross-training involving resistance training (RT), calisthenics, and stretching twice a week for 10 weeks. Pre- and post-intervention measures included height, mass, ATPA, and PA. BMI was calculated and ATPA and PA levels were assessed via questionnaire. The groups did not differ significantly (p > .05) for either pre- or post-intervention regarding BMI, ATPA, and PA. However, BMI and PA levels significantly increased over time for both groups (p ≤ .05). Overall, cross-training in a school setting may be a safe and enjoyable option for physical activity participation. BMI and PA increases were likely the result of the natural growth process and seasonal weather pattern changes, respectively. Nevertheless, the cross-training did not detract from PA levels and may have led to an overall increase in PA levels. As subdomain analyses revealed decreased attitude toward health and fitness in the experimental group, shorter programs involving RT with various protocols are recommended.

Introduction: Sport scientist and strength coaches use resistance training to increase athletic performance and muscle hypertrophy. Improving muscular strength is the most essential task for these scientists, however, how best to identify weakness has yet to be established. The popularity of velocity-based resistance training has recently increased as a method to prescribe resistance training intensity, therefore, the purpose of the study was to identify the characteristics of bench press concentric velocity. It is hypothesized that the velocity output will decrease during the change from the 75% relative load of the 1RM to the 85% relative load of 1RM. It is believed that there will be a greater output of velocity during the 75% set than the 85% set. Methods: Nine female collegiate athletes (18-21 yrs), participated in this study. PUSH™ bands were used to measure barbell velocity during the bench press exercise. Each female was expected to preform 3 sets of 5 repetitions (3x5) at an intensity of 75% and 85% of their 1 repetition maximum (1RM). Only data from repetition 2-4 were used for analysis. Results: The results drawn from data collected supported our hypothesis showing a decrease in velocity among the 85% 1RM test when compared to the 75% 1RM test group. Comparisons were drawn using a t-Test table comprised of PUSH™ Band data. Conclusion: The results supported the hypothesis that this type of technology can identify the load specific velocity to help strength coaches to identify the optimal resistance for certain training program and goals by using collected data with the PUSH™ Band to identify weakness in strength and/or endurance.

Rapid repetitive tapping, like the Foot Tap Test (FTT), slows with age, but the underlying mechanisms are unknown. Purpose: 1. Test the hypotheses that greater performance variability, increased muscle coactivation, and slowed muscle contractile speeds are related to lower foot tap count (FTC) in older adults; 2. Examine the relationship between FTC and physical function in older adults, using the advanced SPPB-A. Methods: 18 (25.0±3.1years, 9F, mean±SD), and 28 (73.4±4.9, 14F) adults were recruited; the later were divided into Higher (HFO) and Lower (LFO) Functioning based on SPPB-A score. Participants performed 10s of rapid tapping (FTT) while seated. A MATLAB program was used to calculate FTC and variability of the intertap-interval (COV-ITI). Contractile speed (rates of force development and relaxation, RFD and RFR) of the dorsiflexor muscles were determined using ballistic contractions. Electromyography was recorded on the tibialis anterior, soleus, and coactivation was calculated based on their agreement. Results: LFO had a lower FTC than Young and HFO (45.9±7.0taps, 54.4±7.5, 53.1±5.7, respectively; p=0.003), and lower COV-ITI than Young (12.3±5.9%, 20.5±8.1, respectively, p=0.009). No associations were found between COV-ITI and FTC. Coactivation was higher in Young than HFO (0.568±0.209, 0.321±0.129) and was negatively related to FTC in older (r2=0.274, p=0.005). The LFO had a slower RFD than Young and FTC was positively related to maximal RFD (r2=0.345, p=0.001) and RFR (r2=0.162, p=0.038) in older adults. In older, FTC was related to SPPB-A (r2=0.329, p=0.001). Conclusions: Greater coactivation during the FTT and slower force development may negatively affect FTC in older adults.

Humans naturally select a point at which to transition from walking to running when gradually increasing locomotor speed. This point is known as the walk-to-run transition (WRT). The WRT is traditionally expressed in terms of speed and is known to occur within a close range of 2.1 m/s, which is an accepted heuristic (i.e., empirically based, rounded) threshold value. Very little research exists defining the WRT in terms of cadence (steps/min) despite the fact that spatial temporal aspects of gait underlying the WRT include this parameter. Preliminary evidence suggests that the WRT may be associated with a cadence of 140 steps/min in adults. This overlooked approach to identifying the WRT may be better than speed because of the simplicity and accessibility of recording cadence in both lab- and free-living settings. Wearable technologies can be used to determine cadence in real-time in a variety of settings, and could be used in the future to expand our current knowledge of the WRT. In turn, this knowledge could be used to inform training practices and/or rehabilitation of gait disorders. The purposes of this secondary analysis of an existing treadmill-based data set were to: (1) identify the optimal WRT cadence threshold, and (2) compare the accuracy of the cadence cutpoint to the previous WRT indicators identified in literature (i.e., speed and Froude number). This secondary analysis focused only on the data collected from the 28 participants (20 men, 8 women) whose protocol was terminated due to selecting to run during the treadmill portion of the larger CADENCE-Adults study. The CADENCE-Adults protocol consisted of a series of five-minute bouts beginning at 0.2 m/s and increasing in 0.2 m/s increments, with each bout followed by two minutes of standing rest. Participants could choose to walk or run each bout. The cadence of the bout during which the participants chose to run was considered the WTR cadence, and ROC analyses were performed to determine the optimal cadence cutpoint. Sensitivity, specificity and overall accuracy were calculated to compare the accuracy of the speed and Froude values from literature to the calculated cadence cutpoint. In addition, these analyses were expanded post hoc to also examine the accuracy of the previously proposed cadence cutpoint from the literature and the speed and Froude cutpoint identified from the dataset. Following analyses, three cadence cutpoints (134, 139, or 141 steps/min) were identified that shared equal overall accuracy (92.9%); therefore, there was no single optimal cutpoint. This also occurred for the speed cutpoints, where both 1.9 and 2.0 m/s shared overall accuracies of 78.6%. The optimal Froude cutpoint identified was 0.46 (82.0% overall accuracy). The rank-order overall accuracy of previously identified cutpoints were: a cadence of 140 steps/min (91.1%), Froude number of 0.5 (76.8%) and speed of 2.1 m/s (66.1%). Based on the identified optimal cadence cutpoints, a heuristic range of running cutpoints was recommended anchored on specificity vs. sensitivity preferences. For researchers interested in identifying episodes more likely to be running behavior (with the preference that very few episodes of walking behavior are mistakenly identified), it would be best to use 140 steps/min. However, if they want to be as inclusive as possible in identifying episodes of running behavior (and can tolerate more mistakenly identified episodes walking behavior), they could use 135 steps/min. When applied to this dataset, 96.0% (24/25) of the individuals who were ≥140 steps/min were running, but this decreased to 92.5% (25/27) with ≥135 steps/min. In conclusion, cadence clearly performed much better in terms of overall accuracy when compared to traditionally used WRT indicators of speed and Froude numbers. The recommended heuristics cadence cutpoint range can be used by researchers who want to evaluate the locomotor patterns of individuals when analyzing free-living step-defined data collected using wearable devices.

OBJECTIVE: The key objective of the present investigation was to compare associations between sagittal abdominal diameter (SAD), waist circumference, and BMI to the oral glucose tolerance test (OGTT), along with fasting glucose, HbA1c, and HOMA-IR, in a nationally representative sample of U.S. adults. The study also analyzed the effect of multiple covariates on the anthropometric and glucose metabolism associations. METHODS: A cross-sectional design, including 3,582 subjects, was used. SAD was assessed using an abdominal caliper. All other data were collected following strict NHANES protocol. The OGTT was the primary variable used to index glucose metabolism. Fasting glucose, HbA1c, and HOMA-IR were also evaluated. RESULTS: Mean ± SE values were as follows: SAD: 22.3 ± 0.1 cm; waist circumference: 98.0 ± 0.4 cm; BMI: 28.6 ± 0.2 kg/m2; OGTT: 113.9 ± 1.0 mg/dL; fasting glucose: 99.6 ± 0.3 mg/dL; HbA1c: 5.4 ± 0.01%; HOMA-IR: 3.2 ± 0.1. SAD consistently emerged as the best predictor of all the indices of glucose metabolism, before and after adjusting for the covariates, and with the sample stratified by gender, race, or age. SAD was not a better predictor of OGTT among normal weight adults and non-Hispanic black adults. CONCLUSION: Obesity, especially abdominal obesity, is strongly related to glucose metabolism and type 2 diabetes. In the present study, SAD was the best anthropometric predictor of glucose metabolism, notwithstanding the high correlations among SAD, waist circumference, and BMI. Due to the ease of taking a SAD measurement, we recommend that healthcare providers consider the use of this simple and inexpensive method to more precisely predict diabetes risk, especially among overweight and obese adults.