International Society of Sports Nutrition Position Stand: Nutritional recommendations for single-stage ultra-marathon; training and racing

Background. In this Position Statement, the International Society of Sports Nutrition (ISSN) provides an objective and critical review of the literature pertinent to nutritional considerations for training and racing in single-stage ultra-marathon. Recommendations for Training. i) Ultra-marathon runners should aim to meet the caloric demands of training by following an individualized and periodized strategy, comprising a varied, food-first approach; ii) Athletes should plan and implement their nutrition strategy with sufficient time to permit adaptations that enhance fat oxidative capacity; iii) The evidence overwhelmingly supports the inclusion of a moderate-to-high carbohydrate diet (i.e., ~60% of energy intake, 5 – 8 g⸱kg−1·d−1) to mitigate the negative effects of chronic, training-induced glycogen depletion; iv) Limiting carbohydrate intake before selected low-intensity sessions, and/or moderating daily carbohydrate intake, may enhance mitochondrial function and fat oxidative capacity. Nevertheless, this approach may compromise performance during high-intensity efforts; v) Protein intakes of ~1.6 g·kg−1·d−1 are necessary to maintain lean mass and support recovery from training, but amounts up to 2.5 g⸱kg−1·d−1 may be warranted during demanding training when calorie requirements are greater; Recommendations for Racing. vi) To attenuate caloric deficits, runners should aim to consume 150 - 400 kcal⸱h−1 (carbohydrate, 30 – 50 g⸱h−1; protein, 5 – 10 g⸱h−1) from a variety of calorie-dense foods. Consideration must be given to food palatability, individual tolerance, and the increased preference for savory foods in longer races; vii) Fluid volumes of 450 – 750 mL⸱h−1 (~150 – 250 mL every 20 min) are recommended during racing. To minimize the likelihood of hyponatraemia, electrolytes (mainly sodium) may be needed in concentrations greater than that provided by most commercial products (i.e., >575 mg·L−1 sodium). Fluid and electrolyte requirements will be elevated when running in hot and/or humid conditions; viii) Evidence supports progressive gut-training and/or low-FODMAP diets (fermentable oligosaccharide, disaccharide, monosaccharide and polyol) to alleviate symptoms of gastrointestinal distress during racing; ix) The evidence in support of ketogenic diets and/or ketone esters to improve ultra-marathon performance is lacking, with further research warranted; x) Evidence supports the strategic use of caffeine to sustain performance in the latter stages of racing, particularly when sleep deprivation may compromise athlete safety

DIFFERENCES IN BASELINE FITNESS LEVELS OF NROTC MIDSHIPMEN BETWEEN FALL 2020 AND FALL 2021

Alexa Jenny Chandler, Harry P. Cintineo, Bridget A. McFadden, Shawn M. Arent, FACSM. University of South Carolina, Columbia, SC. Background: College students in Reserve Officer Training Corps (ROTC) programs must meet physical fitness standards in order to commission as a military officer. While physical fitness training is required during the semester, cadets are expected to continue training during the summer break. However, nationwide closures due to COVID-19 during the spring and summer of 2020 may have impeded training abilities and thereby fitness status of incoming cadets in Fall 2020. The purpose of this analysis was to compare fitness levels of Naval ROTC (NROTC) midshipmen upon return to campus in Fall 2020 (FA20) compared to Fall 2021 (FA21). It was hypothesized the battalion would arrive at a higher fitness level in FA21 due to the accessibility of public exercise facilities over the summer months which were largely unavailable during the 2020 summer months. Methods: NROTC midshipmen completed a battery of fitness tests within one month of arrival to campus in FA20 (N=70; Age = 21 ± 2; 89% male) and repeated testing in FA21 (N=85; Age = 20 ± 2; 80% male). Body mass index (BMI; kg/m2) was calculated from height and weight metrics. Performance tests consisted of a countermovement vertical jump (CMJ) and the 20-meter shuttle run test to estimate VO2max. Linear mixed effects models were used to determine overall battalion differences in BMI, CMJ height, and VO2max FA20 compared to FA21 with an alpha level of 0.05 to determine statistical significance. Results: While there were no differences in BMI (P=0.25), 47.2% of midshipmen were classified as ‘overweight’ in FA20 compared to 43.6 % in FA21. CMJ height was significantly higher at FA21 than FA20 (±1.4 cm; P=0.02) but there were no differences in estimated VO2max (FA20 = 48.8 ±5.2 ml/kg/min; FA21 = 49.2 ± 5.4 ml/kg/min; P=0.45). Conclusions: While there were no differences in aerobic fitness, anaerobic fitness appeared to be higher in FA21. While it is not possible to determine the direct impacts of COVID-19 on fitness levels, it is plausible that pandemic-associated closures prevented strength and power training due to lack of fitness facilities and associated equipment, leading to decreased peak power measured as CMJ height. ROTC programs across the country may need to adjust their training programs upon return to in-person activities to ensure all cadets meet the required fitness standards, especially those related to strength and power

PHYSIOLOGICAL CHARACTERISTICS OF COLLEGIATE TENNIS PLAYERS PRIOR TO PRESEASON

Braxton W. Byrd, Blaine S. Lints, Alexa J. Chandler, Harry P. Cintineo, Bridget A. McFadden, Shawn M. Arent, FACSM. Department of Exercise Science, University of South Carolina, Columbia, SC. BACKGROUND: Muscular power and endurance are both important for tennis players due to the power-endurance nature of the sport. Physiological testing can aid coaches in making training decisions on athlete readiness and adaptations. The purpose of this study was to evaluate baseline physiological and performance characteristics of tennis players and identify relationships between parameters. METHODS: Collegiate tennis players (male [M]: n=7, age = 20.7 ± 1.3 y, height = 186 ± 4 cm, mass = 82.2 ± 4.5 kg; female [F]: n=10, age=19.6 ± 1.3 y, height = 166 ± 5 cm, mass = 65.3 ± 9.2 kg ) participated in preseason testing to assess body composition, reaction time (RT), muscular power, and aerobic capacity. First, body composition (body fat percentage [BF%], fat-free mass [FFM]) was measured by air displacement plethysmography (BOD POD), followed by cognitive (Dynavision D2) and whole-body dynamic (Trazer System) RT. Muscular power was assessed by maximal countermovement jump with hands-on-hips (CMJ) method and aerobic capacity was determined via maximal oxygen consumption (VO2max) testing. Data are presented as mean ± standard deviation and relationships between metrics were assessed using Pearson’s correlations (r) with an alpha-level of 0.05. RESULTS Average BF% and FFM were 10.8 ± 4.0 % and 73.3 ± 3.6 kg for M and 21.6 ± 6.2% and 51.7 ± 6.7 kg for F. Cognitive RT was 0.7 ± 0.1 s for both M and F and dynamic RT was 0.5± 0.0 s and 0.5±0.1 s for M and F, respectively. Average CMJ was 56.4 ± 6.2 cm for M and 41.9 ± 4.4 cm for F and average VO2max was 57.1 ± 5.1 ml/kg/min for M and 47.3 ± 5.8 ml/kg/min for F. BF% was inversely related to both CMJ (r=-0.72; P\u3c0.01) and VO2max (r=-0.77; P\u3c0.01). CONCLUSIONS: Overall, this sample of athletes was lean, although M were relatively leaner than F based on normative data. While RT was similar between sexes, future research should investigate how these parameters relate to on-court tennis performance. CMJ and VO2max should be monitored consistently to assess athlete-readiness and response to training programs. Correlational findings suggest increased BF% may hinder both anaerobic and aerobic performance, as athletes with higher BF% had lower CMJ heights and cardiovascular fitness. Decreasing BF% and increasing FFM may improve overall athlete fitness and therefore positively impact tennis-specific performance

NAVAL RESERVE OFFICERS’ TRAINING CORPS MILITARY PERFORMANCE AND FITNESS CHARACTERISTICS ACROSS ACADEMIC YEARS

Gianna F. Mastrofini1, Alexa J. Chandler1, Blaine S. Lints1, Harry P. Cintineo2, Bridget A. McFadden3, Shawn M. Arent, FACSM1. 1University of South Carolina, Columbia, SC. 2Lindenwood University, Saint Charles, MO. 3Queens College, Queens, NY. BACKGROUND: Navy Reserve Officer Training Corps (NROTC) prepares midshipmen (MIDN) for roles as future military officers. To ensure body composition and fitness standards are maintained, MIDN participate in weekly group physical training. The purpose of this analysis was to determine if there were any differences in MIDN performance across academic years as an estimation of progress during their four years in the NROTC program. METHODS: MIDN (n=63, age=19.8 ± 1.7) completed a battery of tests to assess their physical fitness. Waist-to-hip ratio was calculated from waist and hip circumferences and BMI was calculated from height and weight metrics. MIDN completed maximal countermovement vertical jumps (CMJ) with and without arm swing to determine peak anaerobic power via a digital contact mat. Following, MIDN performed the 20-meter shuttle run test as a field-based estimate of aerobic capacity. Military-specific performance assessments were done as a part of regular NRTOC training. To determine changes across class years, a one-way ANOVA was run on each variable with significance set at p\u3c0.05. Cohen’s d (d) effect size assessed the magnitude of the difference between only the freshmen and senior academic years. RESULTS: No significant differences were found between the academic years for any of the variables assessed: BMI (p=0.274; d=0.259), waist-to-hip ratio (p=0.4237; d=0.629), CMJ with arm swing (p=0.949; d=0.130), CMJ with hands on hips (p=0.927; d=0.830), and aerobic capacity (p=0.753; d=0.063). In the Marine Corp NROTC physical readiness test (PRT), there were no significant differences found for pullups (p=0.106) and 3-mile run time (p=0.079). No significant differences were found in the Navy physical fitness test (PFT), pushups (p=0.473), and 1.5-mile run times (p=0.868). CONCLUSIONS: These findings show that for Fall 2021 the more senior MIDN did not have greater fitness than less senior MIDN. This indicates the current NROTC training model may not effectively improve fitness over the course of a college career, as it would be expected that fitness measures increase throughout four years of training. However, it is possible anaerobic power improves, as shown by the large effect size, but a larger sample size is needed to further investigate this. These results warrant future studies with a larger sample size of NROTC MIDN and longitudinal studies to assess changes over time

INTERNAL WORKLOAD, TRAINING DISTRESS, AND STARTING STATUS IN COLLEGIATE VOLLEYBALL PLAYERS DURING A COVID-19 SEASON

Caroline S. Vincenty, Gabriella Hickman, Alexa J. Chandler, Harry P. Cintineo, Bridget A. McFadden, Shawn M. Arent, FACSM. The University of South Carolina, Columbia, SC. BACKGROUND: Pressure is high among athletes throughout a season to earn starting positions and thus playing time. Starters (S) typically accrue greater internal workloads (IW) than nonstarters (NS) due to more playing time in matches. Heightened IW puts an athlete at increased injury risk or overtraining. While higher IW may negatively affect physical and psychological training distress in S, NS may also exhibit high training distress due to psychological pressure from earning match time. Our purpose was to assess relationships between IW and subjective training distress and to evaluate differences in these metrics between S and NS over a competitive volleyball (VB) season. METHODS: Female collegiate VB athletes (N=15; [S: n=6; NS: n=8]) completed an 11-week modified spring season due to the COVID-19 pandemic. Athletes wore heart rate monitors (Polar Team Pro System) during all team activities to quantify IW via Edwards training impulse (TRIMP). Subjective training distress was monitored weekly via the Multicomponent Training Distress Scale (MTDS). Differences in TRIMP and MTDS scores (total score, depressed moods [DM], vigor [V], physical signs/symptoms [PSS], sleep disturbances [SD], perceived stress [PS], and general fatigue [GF]) between S and NS were assessed via linear mixed effects models. Pearson’s correlations (r) were used to assess relationships between TRIMP and MTDS scores. All significance for analyses were set at P\u3c0.05. RESULTS: There were no main effects of S/NS or group by time interactions for TRIMP, total MTDS, DM, V, PSS, or PS (P\u3e0.05). There were significant group by time effects for SD (P=0.04) and GF (P=0.05). TRIMP was weakly, inversely correlated with total MTDS (r=-0.25, P=0.01), DM (r=-0.22, P=0.02), PSS (r=-0.20, P=0.03), and SD (r=-0.29, P=0.02). However, there were no significant relationships between TRIMP and V, PS, or GF (P\u3e0.05). CONCLUSIONS: While there were no differences in TRIMP or total MTDS, SD and GF changed differently over the season based on starter status. Lack of differences in TRIMP may be attributed to in-game substitutions strategies contributing to workloads. Additionally, the inverse relationship between TRIMP and MTDS was unexpected but may relate to relative fitness of the athlete. Further investigations are warranted to better understand the interactions between starter status, workload, and SD and GF in athletes

MEASURES OF ATHLETE READINESS THROUGHOUT A DIVISION I COLLEGIATE VOLLEYBALL SEASON

Alexa Jenny Chandler1, Mallory Dixon1, Bridget A. McFadden2, Harry P. Cintineo3, Blaine S. Lints1, Gianna F. Mastrofini1, Shawn M. Arent, FACSM1. 1University of South Carolina, Columbia, SC. 2Queens College, Flushing, NY. 3Lindenwood University, St. Charles, MO. BACKGROUND: Volleyball is primarily an anaerobic sport, as players need to perform bursts of high intensity exercise followed by short rest repeatedly throughout a match. Managing athlete workloads to maintain high levels of performance is an important part of team success. The purpose this study was to assess workload, performance, training distress, and sleep, as well as the relationships between these variables. METHODS: Female collegiate volleyball players (n=19) were monitored throughout the 12-week fall 2021 competitive season (T1-T12). Workloads were quantified by a rolling 7-day sum of session rating of perceived exertion (sRPE). Athletes participated in weekly testing to assess physical readiness, training distress, and sleep quality. Physical readiness was assessed by weekly countermovement jump (CMJ). Training distress was determined using the Multicomponent Training Distress Scale (MTDS) composite score and sleep quality was assessed using the Groningen Sleep Quality Score (GSQS). Linear mixed-effects models were used to determine change over time in workload, CMJ, MTDS scores, and GSQS scores with post-hoc tests comparing each timepoint back to T1. Relationships between changes in each metric were assessed via repeated measures correlations. An alpha level of 0.05 was used to determine statistical significance.RESULTS: There were time main effects for sRPE (P\u3c0.001), CMJ (P\u3c0.001), MTDS scores (P\u3c0.001), and GSQS scores (P=0.032). sRPE was significantly lower at T6 (P\u3c0.0001) while there were no differences from baseline in CMJ at any timepoint. MTDS scores were significantly elevated at T5 (P=0.049), T8 (P=0.025), T11 (P=0.001), and T12 (P=0.022) and GSQS scores were higher than baseline at T2-T4, T6-T8, and T10-T12 (P\u3c0.05). There was a significant weak correlation between sRPE and CMJ (r=0.2; P=0.33) but no significant relationships between any other variable. CONCLUSIONS: This study showed fluctuations in subjective training distress and sleep while objective workload and performance measures remained stable throughout the season. Future analyses should investigate the relationship between objective and subjective measures on an individual level, rather than as a team, as some individuals may respond differently to both workload and non-training related stressors

RELATIONSHIP BETWEEN CHANGE IN VO2VT2 AND CHANGE IN 2-MILE RUN TIME

Nathaniel D. Rhoades1, Jacob J. May1, Blaine S. Lints1, Harry P. Cintineo2, Alexa J. Chandler1, Bridget A. McFadden3, Gianna F. Mastrofini1, Shawn M. Arent, FACSM1. 1University of South Carolina, Columbia, SC. 2Lindenwood University, Saint Charles, MO. 3Queens College, New York, NY. BACKGROUND: Resistance training (RT) is widely understood to influence oxygen consumption kinetics during aerobic exercise. While measurement of cardiovascular fitness has focused heavily on maximal oxygen consumption (VO2max), the utility of assessing the second ventilatory threshold (VO2VT2) has gained increasing attention as a relevant metric. The purpose of this study was to identify associations between changes in VO2max and VO2VT2 with changes in 2-mile run times following a 6-week RT intervention.  METHODS: 41 collegiate Reserve Officer Training Corps (ROTC) cadets (n= 11 female; n= 30 male) completed a 6-week RT intervention consisting of 4 sessions per week. VO2max, VO2VT2, and 2-mile run times were assessed pre- and post-intervention. Heart rate (HR) was measured via chest strap during all testing (Polar Electro Inc., Woodbury, NY, USA). Paired sample t-tests were used to evaluate differences in VO2max, VO2VT2, and 2-mile run time pre- and post-intervention. To determine relative intensity of the 2-mile run, paired t-tests were used to compare average HR during the 2-mile run and HRVT2. Pearson-product moment correlations were used to assess relationships between individual changes in VO2max and VO2VT2 with changes in 2-mile run times. An alpha level of 0.05 was used to determine statistical significance. RESULTS: No significant differences were identified pre- to post-testing for VO2max (p \u3e 0.05) or VO2VT2 (p \u3e 0.05). 2-mile run time was significantly different in pre- vs. post-testing (17.64 ± 3.3 vs. 16.82 ± 2.9, p \u3c 0.01). Average HR during the 2-mile run was significantly higher compared to HRVT2 in pre- to post-testing (181.1 ± 9.7 vs. 163 ± 13.2, p \u3c 0.01) (180.3 ± 7.6 vs. 160.8 ± 11.2, p \u3c 0.01). No correlations were identified between changes in 2-mile run times and VO2max (r = -0.18, p = 0.26) or VO2VT2 (r = -0.03, p = 0.86). CONCLUSIONS: Our findings suggest VO2max and VO2VT2 do not have significant predictive value for changes in 2-mile run time following a 6-week RT intervention. Pre- and post-intervention average HR during the 2-mile run was significantly higher than HRVT2, indicating the run was performed at a high intensity. Future research should investigate the value of various physiological metrics in predicting changes in high intensity run performance, particularly after non-aerobic training interventions

PERFORMANCE AND BODY COMPOSITION MEASURES IN MALE TENNIS PLAYERS DURING A COVID-19 MODIFIED COLLEGIATE YEAR

Gianna F. Mastrofini, Alex F. Miller, Megan S. Ward, Harry P. Cintineo, Alexa J. Chandler, Blaine S. Lints, Bridget A. McFadden, Shawn M. Arent, FACSM. University of South Carolina, Cayce, SC. Background: The novel coronavirus (COVID-19) pandemic resulted in nationwide lockdowns and quarantine periods, creating a barrier for athletes to maintain their usual fitness routines. Athletes and coaches needed to adjust training to accommodate for shutdowns and reduced access to typical training modalities. Purpose: The purpose of this study was to determine changes in performance and body composition variables throughout a yearlong COVID-19 modified tennis season in male collegiate athletes. Materials and Methods: Performance and body composition metrics of collegiate male tennis players (N=8) were assessed at the beginning and end of the fall 2020 academic semester [(Pre2020) & (Post2020)] as well as the beginning and end of the spring 2021 semester [(Pre2021) & (Post2021)] during a COVID-19 modified yearlong tennis season. Athletes arrived at the laboratory \u3e2 hours fasted, having abstained from caffeine and vigorous exercise \u3e24 hours prior. Body composition was assessed via air displacement plethysmography to determine percent body fat (%BF) and fat-free mass (FFM). Following a standardized dynamic warmup, athletes completed maximal countermovement vertical jump tests, with both hands on hips (CMJHOH) and arm swing method (CMJAS), using a digital contact mat. This was followed by a whole-body dynamic reaction time (RT) test (Trazer system). A VO2max test was used to determine maximal aerobic capacity and ventilatory threshold (VT). The best of two trials were reported for RT and vertical jump height. Linear mixed-effects models were used to analyze changes over time with significance set at P\u3c0.05. Results: FFM was the lowest Pre2020 compared to all other time points (P\u3c0.001). CMJHOH increased from Pre2020 to Pre2021 (ΔCMJHOH = 2.4 ± 1.2 cm; P=0.045) before returning to baseline values at Post2021. There were no statistically significant changes in %BF, CMJAS, RT, VO2max, or VT (P\u3e0.05). Conclusions: Improvements in lower body power and FFM occurred as the academic year progressed. This may be a result of increased workload demands as athletes returned to structured training following the off-season. These significant improvements may be due to lower baseline values post COVID-19 lockdowns. In addition, the return-to-baseline CMJHOH values at the end of the season may provide an indication of athlete readiness resulting from the cumulative demands of the yearlong tennis season

INTER-LIMB ASYMMETRIES, PEAK POWER, AND INTERNAL TRAINING LOADS IN NCAA DIVISION I FEMALE SOCCER ATHLETES

Drake Dillman, Ryan Albino, Caroline Vincenty, Alex Miller, Alexa J. Chandler, Harry P. Cintineo, Bridget A. McFadden, Shawn M. Arent, FACSM. University of South Carolina, Columbia, SC. INTER-LIMB ASYMMETRIES, PEAK POWER, AND INTERNAL TRAINING LOADS IN NCAA DIVISION I FEMALE SOCCER ATHLETES Dillman, D., Albino, R., Vincenty, C., Miller, A., Chandler, A.J., Cintineo, H.P., McFadden, B.A., Arent, S.M. BACKGROUND: Periodic testing and workload monitoring throughout a competitive season can help athletes and coaches periodize training to optimize performance. In particular, vertical jump testing to assess peak power and inter-limb asymmetries can be used to monitor athlete-readiness. The purpose of this study was to evaluate the relationship between internal training loads (TL), asymmetry rates, and peak power throughout a soccer season. METHODS: National Collegiate Athletic Association (NCAA) Division I female soccer players (N=21) were evaluated at all practices and games using a team-based heart rate monitoring system (Firstbeat Sports, Jyvaskyla, Finland) to assess TL via Banister’s training impulse score (TRIMP). At the beginning of each week, athletes performed a dynamic warmup followed by maximal bilateral (CMJ) and single leg (SL) countermovement vertical jump tests using a hands-on-hips method assessed via a digital contact mat. The best of two trials were used for each jump test. An asymmetry index (ASY) was calculated by dividing dominant by non-dominant SL height. A linear mixed effects model was used to assess changes in CMJ, ASY, and TRIMP throughout the season. Repeated measure correlations were used to determine relationships between weekly changes in TRIMP, CMJ and ASY using an absolute ASY score. Significance was set at p\u3c0.05 RESULTS: Time main effects were observed for weekly changes in TRIMP (p\u3c0.001) and CMJ (p=0.01) over the season. No changes in ASY were observed (p=0.09). There was a significant weak correlation between CMJ and ASY (r=0.17; p=0.04), but no other relationships between TRIMP, CMJ, and ASY (p\u3e0.05). CONCLUSION: Changes in internal workloads and peak power were apparent throughout the season and may influence athlete readiness. Although no changes in ASY were seen, a significant inverse correlation between ASY and peak power was observed, which may impact on-field performance. Declines in peak power along with higher asymmetry rates have been associated with injury risk. Systematic monitoring and periodized testing may aid in athlete-management strategies to mitigate these risks