Purpose: To examine the validity of 2 kinematic systems for assessing mean velocity (MV), peak velocity (PV), mean force (MF), peak force (PF), mean power (MP), and peak power (PP) during the full-depth free-weight back squat performed with maximal concentric effort. Methods: Ten strength-Trained men (26.1 ± 3.0 y, 1.81 ± 0.07 m, 82.0 ± 10.6 kg) performed three 1-repetition-maximum (1RM) trials on 3 separate days, encompassing lifts performed at 6 relative intensities including 20%, 40%, 60%, 80%, 90%, and 100% of 1RM. Each repetition was simultaneously recorded by a PUSH band and commercial linear position transducer (LPT) (GymAware [GYM]) and compared with measurements collected by a laboratory-based testing device consisting of 4 LPTs and a force plate. Results: Trials 2 and 3 were used for validity analyses. Combining all 120 repetitions indicated that the GYM was highly valid for assessing all criterion variables while the PUSH was only highly valid for estimations of PF (r = .94, CV = 5.4%, ES = 0.28, SEE = 135.5 N). At each relative intensity, the GYM was highly valid for assessing all criterion variables except for PP at 20% (ES = 0.81) and 40% (ES = 0.67) of 1RM. Moreover, the PUSH was only able to accurately estimate PF across all relative intensities (r = .92-.98, CV = 4.0-8.3%, ES = 0.04-0.26, SEE = 79.8-213.1 N). Conclusions: PUSH accuracy for determining MV, PV, MF, MP, and PP across all 6 relative intensities was questionable for the back squat, yet the GYM was highly valid at assessing all criterion variables, with some caution given to estimations of MP and PP performed at lighter loads.

Title: Comparing hydration practices of long-distance runners during intended training, an intended event, and an actual event during COVID-19. Context: Prior studies on long-distance runners have yet to compare hydration practices intended in training to an actual event. Optimal hydration strategies and knowledge of EAH was assessed. Objective: The purpose of this research was to assess and compare the self-reported hydration practices of long-distance runners during an intended training run, an intended event, and during an event. Design: Cross-sectional online survey design Setting: 2020 Hyannis, Massachusetts Marathon; Connecticut trail races; online. Participants: There were 46 participants in the Hyannis, 26 participants in the Connecticut trail races, and 203 participants in the long-distance running studies. Main outcome Measure(s): Survey questions addressed hydration practices, including hydration strategies, and volumes consumed before and during a run. Additional data included demographics, training experience, sources of hydration information, and knowledge of EAH. Results: When comparing volumes consumed, higher correlations were found when comparing intended events in all three studies. In other words, runners intended to drink the same in an intended training run and an intended event. More variation was found when comparing intended volumes to actual volumes. All studies showed strong agreement in the selected hydration strategies between the scenarios and most were statistically significant. The “drinking to thirst hydration strategy”, was selected on average 17% of the time for Hyannis marathoners, 30% of the time for Connecticut trail runners, and 23% of the time for long-distance runners. This hydration strategy is recommended to decrease the risk of EAH in lieu of a personalized hydration plan. EAH awareness among runners was reported between 50-59% of the time in all studies. However, there was inconsistency in recognizing contributing and preventive EAH factors. Conclusion: There were differences in hydration practices when comparing an intended training run, an intended event, and an event. This indicates a need for ongoing education on hydration practices and EAH. If runners mimic appropriate hydration practices during training when running in an event, the risk of EAH may be decreased. The limitation of this research is the self-reported nature of historical data.

No description available.

The primary aim of this study was to examine the time course of change in muscle morphology and vertical jump performance in weightlifters preparing for a national competition. The secondary aim of this study is to examine how perceived recovery and stress state corresponds with alterations in training load leading up to competition. Eleven Olympic Training Site weightlifters completed a 4-week peaking phase for a national competition. Body mass, stress and recovery psychometric measures, and unloaded/loaded (20kg) squat jump height (SJH) were measured weekly and at the competition site. Vastus lateralis cross-sectional area (CSA), muscle thickness (MT) and pennation angle (PA) ultrasound measurements were taken prior to and following the training protocol. In competition, 6 athletes set a personal best in snatch, clean and jerk and/or total. These results suggest that improvements in the loaded SJ and psychometric measures correspond to successful competition performance in some weightlifters. Notably, most weightlifters appeared to be peaked within 3 days of competition.

Postural stability assessment tools are one of the many ways concussions can be assessed and return to play decisions can be made; two of which are the Balance Error Scoring System (BESS) and force plate technology. OBJECTIVE: Validate the modified BESS used by Utah State University by comparing it to equivalent tests on the NeuroCom Balance Manager System. METHODS: 114 current or previous Utah State football players ranging in age from 18-24. Each athlete conducted a baseline BESS test during their pre-participation physical and NeuroCom testing was conducted during the summer of 2011. NeuroCom testing included a modified Clinical Test of Sensory Interaction on Balance (mCTSIB) both on a firm and foam surface, a single leg stance test with eyes open and closed on both a firm and foam surface, and a tandem walk test where end sway was recorded. BESS testing was done depending on when the athlete arrived at Utah State. Correlations were reported for athletes that arrived for the current year and also for the athletes that arrived for any year prior to that. A Welch's T-Test was conducted to analyze any differences between the two groups. The tandem stance on the foam condition for the BESS had a statistically significant difference, so that variable was excluded and the adjusted correlations were then reported. There were eight correlation conditions that were determined by the individuals who could and could not complete the entire time on the single leg stance with eyes closed on a firm as well as a foam surface. RESULTS: The only variable associated with the NeuroCom Balance Manager that had consistent correlations with the composite BESS score was the CTSIB foam condition; with a 0.28 correlation with individuals regardless of single leg stance with eyes closed, 0.39 with individuals who completed the whole time on the firm without consideration for the foam, 0.27 with individuals who did not complete the whole time on the foam without consideration for the firm and 0.39 with individuals who could complete the whole time on the firm but not on the foam. CONCLUSION: There appears to be some correlation with CTSIB foam conditions and the composite BESS.

Literature suggests that the original and "pure" elements of cross country course design have faded through time; in order to wholly enhance course design the original elements must be preserved and united with desired modern course elements. "Pure" sport is defined by an athlete's struggle and persistence that occur amidst tough competition, rugged course elements, and physical pain. In addition to identifying the desired elements through literature review, case studies, and self-experience of cross country course design, it was necessary to confirm the desired elements through interviewing eight key informants. The key informants were renowned and accomplished NCAA cross country coaches selected to represent a wide geographic. These eight informants were interviewed to unveil which elements of cross country courses were desired, important, essential, would advance design, and are underutilized and present in their favored courses. The results from the interviews confirmed a deep desire for enhanced course design by unionizing the elements present in the "pure" sport of cross country with contemporary desired elements. The new "pure" sport of cross country can be obtained through the utilization of the elements revealed within this thesis. Designing courses that will provide unchanged emotions from the "pure" sport of cross country, yet do not incorporate excessively rough course elements, will be the new "pure" sport of cross country. Overall, the results show designing for the athlete, which includes safety, well defined routing and proper carrying capacity, an accomplished sense of place, advanced technologies and facilities, sport appropriate and safe footing and reasonable terrain, and spectator engagement, would considerably improve design. In order to preserve the "pure" sport of cross country while also integrating modern desired and necessary elements, course designers must use pioneering design methods in order to incorporate all of the desired elements. The main objective of this research was accomplished and has established a foundation upon which subsequent research efforts may begin. This work serves as a catalyst to improving cross country course design by attaining the knowledge of proper, intensified, and innovative design.

No description available.

No description available.

Purpose: The purpose of this training, monitoring study was to investigate how alterations in training variables affect changes among underlying mechanisms of performance and weightlifting performance and whether certain variables are better suited for monitoring the training process than others. Additionally, the importance of including barbell displacement in volume load (VL) calculations was investigated. Subjects: Seven (4 males, 3 females) competitive weightlifters participated in the study dealing with alterations of underlying mechanisms and performance while 8 weightlifters (5 males, 3 females) participated in the investigation of exercise displacement. Methods: The weightlifters participated in a 20-week periodized resistance training plan. Measurements of maximal strength and explosive strength from the isometric mid-thigh pull (IMTP) and static jumps (SJ) with 0kg, 11kg, and 20kg were taken toward the end of each training block (weeks 1, 6, 10, 13, 17, and 20). Weightlifting performance was measured at weeks 0, 7, 11, and 20. The detailed monitoring of VL consisted of recording the load, rep count, and with and without displacement for every set for 20 weeks. Results: Very strong correlations were displayed between weightlifting performances and isometric rate of force development (RFD), isometric peak force (PF), and peak power (PP) at 0kg, 11kg, and 20kg. During periods of higher volume loads RFD was depressed to a much greater extent than peak force (PF). For the males, similar to RFD, JH at 20kg responded in a manner fitting an expected fatigue response compared to JH at 0kg and 11kg. VL correlated very strongly to VL with displacement; however, statistically significant differences existed for percent change (4 of the 7 time periods measured) Conclusions: PF is more resistant to volume alterations than RFD and JH at 20kg. Thus RFD and JH at 20kg appear to be superior monitoring metrics. The testing period in which preparedness was the highest happened in concert with a taper. Based on correlations, PF, RFD, and PP are variables on which coaches should focus for enhancing performance. A strong relationship exists between VL and VL with displacement; however, changes from one period to the next are not always the same.

The objectives of this dissertation were to investigate the utility of cf-DNA as a marker of systemic inflammation, fatigue, and training status in a long-term athlete monitoring program (LTAMP). In study one, cf-DNA, other biochemical markers, volume load, and training intensity were measured in weightlifters over 20 weeks. The changes and relationships between these variables were investigated in order to determine which variables may be indicative of an athlete’s training status. In study two, cf-DNA, other biochemical markers, and session rating of perceived exertion (sRPE) were measured over the course of a 15-week soccer season in order investigate the utility of cf-DNA as an indicator of systemic inflammation and fatigue. In study one, CK was statistically greater T2 than T4, T5, and T6 at p = 0.015, 0.025, and 0.030 respectively. cf-DNA %Δ was correlated with CRP percent change and BF% (r = 0.86 and r = 0.91 respectively). The correlation between cf-DNA and CRP suggests that cf-DNA may be a valuable indicator of inflammation. Upon further visual inspection, cf-DNA and CRP also appeared to rise and fall with changes in volume load with displacement (VLwD). In study 2, G1, cf-DNA (P = 0.001), CRP (P = 0.000), CK (P = 0.003), cf-DNA %Δ (P = 0.002), CRP %Δ (P = 0.002), and CK %Δ (P = 0.002) were all significantly higher than T1 at T2 and T3. In G2, CRP (P = 0.057) and CRP %Δ (P = 0.039) were significantly higher at T2 than T1. Despite the lack of statistically significant differences across all 3 testing times, cf-DNA %Δ, CRP %Δ, and CK %Δ increased throughout the season in G1. In G2, cf-DNA %Δ, CRP %Δ, and CK %Δ were all higher at T2 and T3 than T1 but fewer significant differences were present, potentially a result of the lower sRPE values in G2 versus G1.These results suggest that cf-DNA may a useful marker to reflect accumulated training and competitive stressors. The correlation between cf-DNA and CRP in study 1 suggests that cf-DNA may be a valuable indicator of inflammation.