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A Popularized Measure Of Anaerobic Capacity May Not Be Valid In Short-Duration Exercise
Get PDFThe gold standard measure of anaerobic contribution is accumulated oxygen deficit (AOD). Calculating AOD is time consuming, as it requires several submaximal exercise tests to estimate oxygen demand. Recent studies have proposed an alternative AOD for measuring anaerobic contributions: this ‘AOD_alt’ provides separate measures of phosphocreatine and glycolysis contributions and requires only one exercise test. PURPOSE: This study aimed to determine the validity of AOD_alt as a measure of anaerobic contribution during constant power, severe intensity, cycle ergometer exercise of different durations. METHODS: Seven women (age 23 ± 3 y, height 169 ± 8 cm, weight 67 ± 12 kg) and thirteen men (22 ± 2 y, 182 ± 9 cm, 78 ± 10 kg) performed three constant power, severe intensity, cycle ergometer tests, terminated after either 3 min, 6 min, or 9 min, with the order of durations determined using randomization. AOD was calculated as the difference between the estimated oxygen cost of exercise and the accumulated oxygen uptake. AOD_alt was calculated as the sum of the phosphocreatine contribution, estimated from post-exercise VO2, and the glycolysis contribution, estimated from post-exercise blood lactate concentration. Values for AOD and AOD_alt were compared using a two-way repeated-measures analysis of variance (ANOVA; Method x Duration), post hoc t-tests, and Pearson correlation (significance at p \u3c 0.05). RESULTS: The results of the ANOVA revealed significant main effects for Method (AOD \u3e AOD_alt) and for Duration (anaerobic contribution greater in longer tests). There was also a significant interaction effect (p = 0.003). Results of post hoc tests revealed that, in the 9 min tests, AOD_alt was not different from AOD (p = 0.314), correlation r = 0.923 (p \u3c 0.001); in the 6-min tests, AOD_alt was not different from AOD (p = 0.332), correlation r = 0.918 (p \u3c 0.001); and in the 3-min tests, AOD_alt was greater than AOD (p \u3c 0.005), correlation r = 0.765 (p \u3c 0.001). CONCLUSION: These results suggest that AOD_alt may be a valid measure of anaerobic contribution during constant power, severe intensity, cycling exercise of 6 or 9 min duration. However, its applicability to exercise of shorter durations, such as 3 min, may be limited and warrants further research
Estimating Minute Ventilation and Inspiratory Flow to Trigger Exercise-Induced Laryngeal Obstruction (EILO) in Pediatric Patients
Get PDFExercise-induced respiratory symptoms hinder exercise participation and performance in adolescents. One cause is exercise-induced laryngeal obstruction (EILO). While EILO pathology is poorly understood, high airflow rates through the larynx appear necessary to elicit an episode. Exercise above 75% of peak work capacity reliably triggers EILO; however, the minute ventilation (V̇E) and mean inspiratory flow rates (VT/Ti) to trigger EILO are unknown. This information could influence diagnostic testing protocols, exercise prescriptions, and training programs. PURPOSE: The purpose of this ongoing study is to estimate the V̇E and VT/Ti required to trigger laryngeal closure among pediatric patients. METHODS: We screened 39 existing patients with an EILO diagnosis. After excluding patients with missing videos or gas exchange data and those whose diagnosis we could not confirm, we used records from 16 (f = 15, age = 14.6 ± 1.2 years, V̇O2peak = 39.4 ± 6.6 mL·kg·min-1) patients in this preliminary analysis. We will add patients until we reach a sample size of 60. We reviewed charts and analyzed videos from a continuous laryngoscopy during exercise with cardiopulmonary exercise test (CLE-CPET), where a flexible laryngoscope records the behavior of the larynx during treadmill running. Obstruction is graded on a 0 to 3 scale at the glottic and supraglottic levels with a score of ≥2 in either category considered pathologic. We estimated the mean V̇E and VT/Ti to trigger a CLE score of ≥2 among patients with supraglottic, glottic, and mixed-type EILO. We did not perform inferential statistics due to the preliminary nature of this analysis. RESULTS: Ten patients (62.5%) had supraglottic, two (12.5%) had glottic, and four (25%) had mixed-type EILO. Mean V̇E to trigger any type of EILO (n =16) was 60.7 [95% CI: 54.8; 66.3] L·min-1, which equaled 52.5 [47.8; 57.6] % of Maximal Voluntary Ventilation (MVV), and 80.4 [74.0; 86.5] %V̇Epeak achieved in the test. A supraglottic CLE score of 2 (n = 14) appeared to be triggered at a lower V̇E (60.8 [53.9; 67.8] L·min-1;53.1 [48.2; 58.4] %MVV; 79.4 [72.8; 86.1]) than a glottic CLE score of 2 (72.2 [52.1; 104.0] L·min-1;61.0 [47.2; 79.2] %MVV; 92.0 [86.5; 97.0] %V̇Epeak, n = 5). The lowest V̇E to trigger any kind of EILO was 42.0 L·min-1, 39.5 %MVV, and 58.2 %V̇Epeak.EILO was triggered at or below a V̇E of 70 L·min-1and 60 %MVV in most of our patients (81.25%) and at a V̇E of 82.3 L·min-1and 77 %MVV or below in all patients. Mean VT/Ti to trigger any type of EILO was 2.63 [2.33; 2.93] L·sec-1, which equaled 77.8 [70.5; 85.6] %VT/Tipeak. Again, VT/Ti values eliciting a glottic score of 2 (2.87 [2.09; 4.05] L·sec-1;87.5 [78.1; 96.6] %VT/Tipeak) appeared to be higher than those triggering a supraglottic score of 2 (2.66 [2.33; 3.00] L·sec-1;77.2 [68.9; 85.0] %VT/Tipeak). CONCLUSION: A diagnostic exercise test that does not elicit sufficiently high V̇E is not adequate for detecting the presence of EILO. In our preliminary data a VE of 82 L·min-1 and 77 %MVV was necessary to ensure all patients exhibited EILO. Once confirmed in a larger sample, clinicians and researchers can use these estimates to design exercise protocols that elicit sufficient V̇E
Heart Rate Variability After Different Orders of Upper- and Lower-Body Resistance Exercise in Men
Get PDFAcute resistance exercise (RE) has been shown to induce similar impacts on heart rate variability (HRV) between upper- and lower-body RE. However, different orders of combined upper- and lower-body RE on HRV are unknown. PURPOSE: To compare the different orders of upper-and lower-body RE on HRV in young men. METHODS: Thirty-two young men (23±4 years old) completed the study. HRV was expressed as natural logarithm (Ln), and included Root mean square successive difference (LnRMSSD), the proportion of NN50 divided by the total number of NN (R-R) intervals (LnPNN50), total power (LnTP), low frequency power (LnLF), and high frequency power (LnHF), and was assessed at rest, 15-20 (R1), and 25-30 (R2) minutes after either order of upper- and lower-body RE at 75% 1-repetition maximum for 3 sets of 10 repetitions with 1.5- and 2-minute rests between sets and exercises, respectively. The upper- and lower-body RE (UL) condition performed latissimus dorsi pulldown and incline chest press first and then knee extension and knee flexion while the lower- and upper-body RE (LU) condition performed knee extension and knee flexion first and then latissimus dorsi pulldown and incline chest press. A 2-way repeated measure ANOVA was used to determine the effect of different orders across time on HRV. RESULTS: There were no significant 2-way interactions for any variables. There were significant (p\u3c0.05) main effects of time for heart rate (UL: Rest: 62±6, R1: 89±14, R2: 89±14; LU: Rest: 63±6, R1: 90±13, R2: 89±13), LnRMSSD (UL: Rest: 4.01±0.43ms, R1: 2.86±1.05ms, R2: 2.85±1.06ms; LU: Rest: 4.00±0.54ms, R1: 2.61±0.78ms, R2: 2.62±0.79ms), LnPNN50 (UL: Rest: 3.52±0.69, R1: 0.62±1.74, R2: 0.62±1.74; LU: Rest: 3.71±0.34, R1: 0.57±1.84, R2: 0.60±1.88), LnTP (UL: Rest: 78.5±0.8ms2, R1: 7.1±1.2ms2, R2: 7.1±1.3ms2; LU: Rest: 8.6±0.9ms2, R1: 7.3±1.7ms2, R2: 7.3±1.7ms2), LnLF (UL: Rest: 6.8±1.1ms2, R1: 5.5±1.3ms2, R2: 5.4±1.3ms2; LU: Rest: 6.8±1.2ms2, R1: 5.7±1.8ms2, R2: 5.7±1.8ms2), and LnHF (UL: Rest: 8.0±1.1ms2, R1: 5.1±1.9ms2, R2: 5.0±1.9ms2; LU: Rest: 7.9±1.2ms2, R1: 5.0±2.3ms2, R2: 5.1±2.4ms2) such that they increased at R1 and R2 compared to rest after UL and LU. CONCLUSION: These data suggest that acute combined upper- and lower-body RE significantly increases HRV in young men regardless orders of combined upper- and lower-body RE
Age-Related Changes in Memory Performance in Memory Athletes
Get PDFAge-related decline in cognition is a well-documented phenomenon characterized by marked reductions in working and episodic memory. Memory athletes are individuals competing in a variety of memory sports. They exhibit exceptional and remarkable recall and cognitive performance. In spite of the extraordinary cognitive prowess exhibited by memory athletes, there is very little information available regarding the effects of aging on memory performance in this unique group. PURPOSE: This study investigated age-associated changes in memory performance in memory athletes competing in the memory championship events. METHODS: Among all the memory competitions, we examined performance trends in the 5-minute and 15-minute number events (memorizing as many random digits as possible in a selected amount of time) at Memory Championships from 2010 to 2024. These events were selected for their linear scoring models and consistent evaluation criteria across all ages. Participants were categorized into four age groups: junior (≤17), young (18–39), middle-aged (40–59), and senior (60+). The top 30 performers in each category were included in the analysis. Both cross-sectional and longitudinal analyses were used. RESULTS: Polynomial regression analysis revealed an inverted U-shaped relationship between age and performance. Memory performance increased from junior to young categories and gradually decreased to middle-aged and senior categories. The peak performance ages for the 5-minute and 15-minute number events were 28.4 and 29.2 years. Compared with peak performance, memory scores declined 22% at age 40, 56% at age 50, and 74% at age 60 in the 5-minute number events. These trends were similar in the 15-minute event. Violin plots indicated that middle-aged participants exhibited more consistent performance across both events, reflected in a narrower vertical spread and tighter horizontal distribution. In contrast, seniors showed greater variability, as evidenced by a broader vertical and horizontal spread in both disciplines. A one-way ANOVA confirmed the significant relationship between age and performance (p\u3c0.01). CONCLUSION: In competitive memory athletes, memory performance improves from junior to young, reaching peak performance around the late 20s. Subsequently, memory performance declines gradually and markedly with advancing age in competitive memory athletes with highly trained memory systems
Racial Impacts of Cerebral Vascular Responsiveness to Sympathetic Nervous System Activation
Get PDFRacial disparities have been observed in the vasoconstrictor response of peripheral arteries in skeletal muscle circulation following activation of the sympathetic nervous system (i.e., sympathetic vascular transduction). Specifically, non-Hispanic Black (BNH) individuals exhibit an enhanced vasoconstrictor response compared to non-Hispanic White (WNH) individuals. These differences may contribute to the higher incidence of hypertension and cardiovascular events observed in BNH populations. Additionally, BNH individuals face an increased risk and prevalence of various cerebrovascular and neurocognitive disorders. However, it remains unclear whether the heightened skeletal muscle vascular transduction response extends to the cerebral circulation. The Cold Pressor Test (CPT), a common method for inducing sympathetic nervous system activation, elicits significant cardiovascular and vascular reactions, including vasoconstriction. PURPOSE: This study aimed to investigate potential racial differences in cerebral vascular responses to sympathetic activation through the CPT in WNH and BNH individuals. METHODS: Thirteen non-Hispanic Black (BNH) participants (age: 21.07 ± 3.12 years, BMI: 23.72 ± 4.17 kg/m²) and nine non-Hispanic White (WNH) participants (age: 21.89 ± 3.26 years, BMI: 24.67 ± 3.97 kg/m²) took part in this study. Participants were positioned in a supine posture, and baseline (BSL) measurements were recorded over a six-minute period. Following baseline data collection, a sympathetic stimulus was applied by having participants submerge their hand in an ice water slurry for 2 minutes. Continuous measurements of middle cerebral artery blood velocity (MCAVmean) and non-invasive, beat-to-beat mean arterial pressure (MAP) were obtained throughout the protocol. Cerebral vascular tone was evaluated as cutaneous vascular conductance (CVCi; MCAVmean/MAP), with averages calculated for the final 30 seconds of both the BSL and Cold Pressor Test (CPT) phases. RESULTS: CVCi decreased significantly during the final 30 seconds of the Cold Pressor Test (CPT) in both the BNH and WNH groups (p \u3c 0.001 and p = 0.007, respectively). However, no significant differences were observed between BNH and WNH participants at either baseline (p = 0.10) or during the last 30 seconds of CPT (p = 0.24). CONCLUSIONS: The hypothesis that both WNH and BNH individuals would experience a significant reduction in CVCi was confirmed. However, the expectation that BNH individuals would show a greater reduction in CVCi from baseline compared to WNH individuals was not supported by the data
Barefoot Running Alters Spatiotemporal Nonlinear Variability Compared to Shod
Get PDFRunning has been an important aspect of human life for thousands of years. Running continues to be a very popular activity among nearly all non-sedentary, healthy individuals. Modern athletic shoes are designed to reduce impact forces on the foot, and ultimately the body. Shoe manufacturers accomplish this by providing a cushioned shoe midsole to absorb the impact forces (Yu & Kramer, 2021). The contrast of the cushioned shoe compared to the stiffness of barefoot running has great influence on ones running mechanics. The barefoot runner often adopts a forefoot or midfoot striking pattern while decreasing their overall vertical ground reaction force. Even with these adaptations, the barefoot movement of recent past, resulted in an increase in running injury, over the already high rates of injury associated with running. Understanding the differences in the organization of lower extremity running variability from a nonlinear perspective, could provide insight into performance and injury risk (Thompson et al, 2014). PURPOSE: The purpose of our study was to determine differences in nonlinear spatiotemporal variability when running barefoot and in footwear METHODS: For our study, twenty individuals (n = 20, Age = 21 ± 1.1 years, Height = 68.2 ± 3.5 in., Weight = 150.25 ± 24.7 lbs.), completed two, three-minute running trials on a treadmill in our biomechanics lab. The trials included running at their self-selected running speed while barefoot and while wearing shoes. A dependent t-test was used to determine the differences in the nonlinear spatiotemporal variability for the footwear conditions. RESULTS: There were significant differences in stride time DFA-α (barefoot (M=8.3, SD=0.19), shod (M=7.1, SD=.21)), stride length sample entropy (bare (M=1.70, SD=0.27), shod (M=1.80, SD=0.3)), and step length sample entropy (bare (M=1.54, SD=0.41), shod (M=1.64, SD=0.41)) between the barefoot and shod conditions. (p \u3c .05). There were no other significant differences. CONCLUSION: Not only does running barefoot alter one’s mechanics, but it also alters the structure of variability while running. Nearly all runners are prone to injury, so further investigation into the structure of variability during running is warranted. Future studies should investigate the influence that maximally cushioned and carbon fiber plated footwear has on the structure of running variability
UA19/16/1/1 2025 Hilltopper Baseball Media Guide
Get PDF2025 baseball media guide produced by WKU Athletic Media Relations, includes athletic records and statistics, photographs, schedule and information regarding opponents
Age of Anaerobic, Aerobic, and Skill-Based Olympic Athletes 1988 - 2024
Get PDFInternational Journal of Exercise Science 18(3): 404-414, 2025. The age at which athletes compete at a high-level provides understanding of human physiology, development, aging and skill refinement. The Olympics, with high-level performances across events with differing metabolic demands, provide unique data for analysis of optimal performance age given the type of performance required. The aim of this study was to classify Olympic events from 1988-2024 into aerobic, anaerobic, mixed, or skill, and compare male and female athlete ages in each classification. Events of maximal effort under 2-minutes duration were classified as anaerobic. Events longer than 5 minutes were classified as aerobic with those 2-5 minutes duration classified as mixed. Other events that are unlikely to stress aerobic or anaerobic metabolic systems were classified as skill. Athlete age was 24.1 ± 4.6 years for anaerobic, 26.8 ± 4.7 years for aerobic, 24.8 ± 4.6 years for mixed, and 27.8 ± 6.9 years for skill. When separated by sex, female athletes were younger in each classification. Male anaerobic athletes (24.7 ± 4.2) were younger than aerobic (26.9 ± 4.6) and skill (28.9 ± 6.9), but similar in age to mixed athletes (25.0 ± 4.4). Female anaerobic athletes (23.2 ± 5.0) were younger than aerobic (26.7 ± 4.8), skill (26.4 ± 6.5), and mixed (24.4 ± 4.8). Male Olympic athletes in skill-based events that do not stress energy systems compete at older ages than those in events that tax physiologic systems. Female Olympic aerobic and skill athletes, compete at older ages than those in events requiring a significant anaerobic contribution. This analysis provides evidence that event demands likely differ by classification and sex and therefore influence performance age
Evaluation of Valid VO2max Criteria for Graded Exercise Testing in Cancer Survivors
Get PDFInternational Journal of Exercise Science 18(5): 443-455, 2025. Cardiovascular fitness (VO2max) predicts all-cause mortality and is vital to assess in cancer survivors (CS) for individualized exercise prescriptions. Metabolic carts confirm VO2max with respiratory exchange ratio (RER) \u3e1.10; other VO2max criteria include ≤10 beats/minute of maximal predicted heart rate and/or a rating of perceived exertion (RPE) of \u3e8 on the Modified Borg Scale. Another suggested criterion is respiratory frequency (Rf) \u3e 40 breaths per minute. These criteria are assumed applicable for all populations, but due to cancer-related toxicities, frequency and validity of traditional VO2max criteria usage in CS remains unconfirmed. The purpose was to evaluate the frequency of VO2max criterion achievement of RER and alternate maximal criteria using HR, RPE, and Rf in CS. Forty CS performed three graded exercise tests (GXT) using gas analysis, totaling 111 GXTs. Max RER, HR, RPE, and Rf were measured. Differences in successful VO2max criterion achievement frequency were assessed using a Cochran’s Q test and Pairwise Comparison Dunn test with Bonferroni adjustment. Maximal criteria were successfully met in 84%, 79%, 92%, and 43% of trials when evaluating RER, HR, RPE, and Rf, respectively. Significant differences occurred between Rf and all other measures (p \u3c 0.001); no significant differences occurred between RER, HR, RPE. Traditional VO2max criteria may be feasibly obtained and used in CS; HR and RPE are valid alternatives to RER, but Rf is not. The equivalency between RER, RPE, and HR suggests metabolic carts may be unnecessary for CS during maximal testing, increasing accessibility and validity of VO2max values
Program-Level Evaluation of One-on-One and Team-Based Mental Performance Services Among Collegiate Student-Athletes
Get PDFStudent-athletes navigate complex physical, psychological, and social demands, prompting increased integration of mental performance (MP) services in collegiate athletics. However, program-level evaluations remain limited. PURPOSE: To assess the effects of one-on-one and team-based MP services on student-athlete outcomes during the Fall 2024 semester. METHODS: A total of 128 student-athletes (22% response rate) completed a post-season Qualtrics survey. Of these, 82 participated in one-on-one sessions and 68 in team sessions. Self-reported pre- and post-intervention ratings were collected retrospectively in Spring 2025 using custom 10-point Likert-type items assessing athletic performance, mindset, well-being, leadership, sport experience, and team culture. Paired-sample t tests were conducted, and Cohen’s d was calculated in MATLAB to assess change. RESULTS: For one-on-one sessions, mindset improved by 60% (M = 4.90 to 7.83), t(69) = 12.46, p \u3c .001, d = 1.49; athletic performance by 37% (M = 5.76 to 7.89), t(65) = 11.00, p \u3c .001, d = 1.35; well-being by 31% (M = 6.20 to 8.09), t(65) = 9.29, p \u3c .001, d = 1.14; sport experience by 26% (M = 6.37 to 8.00), t(67) = 8.77, p \u3c .001, d = 1.06; and leadership by 27% (M = 5.83 to 7.41), t(63) = 7.52, p \u3c .001, d = 0.94. In team sessions, personal mindset improved by 40% (M = 5.75 to 8.03), t(58) = 9.56, p \u3c .001, d = 1.24; team mindset by 35% (M = 6.03 to 8.14), t(62) = 9.37, p \u3c .001, d = 1.18; personal athletic performance by 27% (M = 6.19 to 7.88), t(57) = 7.67, p \u3c .001, d = 1.01; team culture by 21% (M = 6.94 to 8.42), t(61) = 7.46, p \u3c .001, d = 0.95; and team athletic performance by 22% (M = 6.59 to 8.05), t(57) = 5.89, p \u3c .001, d = 0.77. Across five consultants, the mean recommendation rating was 9.00 (SD = 1.34, 95% CI [8.70, 9.30]). CONCLUSION: MP services were associated with statistically and practically significant gains across psychological skills, performance-related functioning, and interpersonal or cultural domains. While findings are promising, future research should address the low response rate, retrospective design, and potential self-selection bias, and should examine the effects of dual participation in one-on-one and team-based services, which were not included in the present analysis