Monitoring training, performance, biomarkers, and psychological state throughout a competitive season: a case study of a triathlete.

INTRODUCTION: Ironman triathletes undergo high workloads during competition preparation which can result in nonfunctional overreaching or overtraining syndrome if not matched with adequate recovery. PURPOSE: The purpose of this case study was to observe changes in physiological and psychological status over the course of a competitive season in a free-living triathlete. METHODS: The subject was a 41-year-old triathlete competing in three 113.1-km events. Over the course of a 40-week period, the participant arrived at the laboratory every 4 weeks and underwent body composition testing via air displacement plethysmography, a blood draw for analysis of various biomarkers, and a treadmill-based lactate threshold test. Workload during training and competitions was monitored via a wearable heart rate-monitoring device. RESULTS: Throughout the season, training volume remained high (12.5 ± 3.4 h/week) and body mass and fat-free mass (FFM) continuously decreased, while biomarkers including cortisol, testosterone, and markers of immunological status exhibited minor changes. Laboratory performance remained relatively consistent, while competition performance continually improved. Following the completion of the competitive period, training volume decreased, FFM remained below baseline levels, free cortisol increased, and both free and total testosterone decreased. CONCLUSIONS: Workload and recovery seem to have been properly managed throughout the season, evidenced by minimal fluctuations in endocrine and immunological markers. The reason for changes observed in testosterone, cortisol, and body composition following the last competition is unclear, though it may be attributed to changes in stressors and recovery practices outside of training. It is recommended that athletes follow a structured plan during the transition period into the offseason to ensure recovery of physiological state and to set up a productive offseason.

Effects of Minimal-Equipment Resistance Training and Blood Flow Restriction on Military-Relevant Performance Outcomes.

ABSTRACT: Cintineo, HP, Chandler, AJ, Mastrofini, GF, Lints, BS, McFadden, BA, and Arent, SM. Effects of minimal-equipment resistance training and blood flow restriction on military-relevant performance outcomes. J Strength Cond Res 38(1): 55-65, 2024-This study compared minimal-equipment resistance training (RT) with and without blood flow restriction (BFR) to traditional-equipment RT on performance and body composition changes over 6 weeks. Reserve officers' training corps cadets and midshipmen (N = 54, 40.7% female) were randomized into traditional-equipment RT (TRAD), minimal-equipment RT (MIN), or minimal-equipment RT with BFR (MIN + BFR). Performance and body composition were assessed pretraining and post-training, and measures of intensity and workload were evaluated throughout. Performance assessments included the army combat fitness test (ACFT), countermovement vertical jump, 3RM bench press, and V̇O2max; body composition measures included body fat percentage, fat-free mass, and muscle and tendon thickness. All groups trained 4 days per week after a full-body routine. Data were analyzed by mixed-effects models (α = 0.05). Group-by-time interactions for 3RM deadlift and 3RM bench press (p < 0.004) showed larger improvements for TRAD compared with MIN and MIN + BFR. Time main effects for all other performance variables, body fat percentage, fat-free mass, and muscle thickness (p ≤ 0.035) indicated improvements in all groups. A group-by-time interaction for blood lactate (p < 0.001) and group main effects for heart rate (p < 0.001) and workload variables (p < 0.008) indicated higher intensity and workload for MIN and MIN + BFR compared with TRAD. A sex-by-time interaction for 3RM deadlift (p = 0.008) and sex-by-group-by-time interaction for 3RM bench press (p = 0.018) were also found. Minimal-equipment RT improved performance and body composition, although strength improvements were greater with traditional equipment. Minimal-equipment RT and minimal-equipment RT with BFR exhibited higher exertion levels than TRAD, although adaptations were similar. Overall, individuals can improve performance and body composition using portable, field-expedient RT equipment.

Power, Endurance, and Body Composition Changes Over a Collegiate Career in National Collegiate Athletic Association Division I Women Soccer Athletes.

ABSTRACT: McFadden, BA, Bozzini, BN, Cintineo, HP, Hills, SP, Walker, AJ, Chandler, AJ, Sanders, DJ, Russell, M, and Arent, SM. Power, endurance, and body composition changes over a collegiate career in National Collegiate Athletic Association Division I women soccer athletes. J Strength Cond Res 37(7): 1428-1433, 2023-The purpose of this study was to determine longitudinal changes in fitness and body composition throughout athletes' 4-year collegiate soccer careers. Performance testing occurred before preseason during freshman, sophomore, junior, and senior year in 17 female Division I soccer players. Body composition was assessed through air-displacement plethysmography to determine percent body fat (%BF), fat-free mass (FFM), and body mass (BM). Maximal countermovement vertical jump height was assessed through contact mat using arm swing (CMJ AS ) and hands-on-hips (CMJ HOH ) methods to calculate power (CMJ watts / HOHwatts ). Aerobic capacity (V̇ o2 max) and ventilatory threshold (VT) were assessed by indirect calorimetry during a maximal graded exercise test on a treadmill. Linear mixed models were used to assess changes across academic years ( p < 0.05). No changes occurred in %BF, BM, V̇ o2 max, VT, CMJ AS , or CMJ watts . A time main effect was seen for FFM ( p = 0.01) with increases from freshman to senior ( p = 0.02). Time main effects were observed for CMJ HOH ( p < 0.001) and CMJ HOHwatts ( p < 0.001) with increases from freshman to junior (CMJ HOH,p = 0.001; CMJ HOHwatts , p = 0.02) and senior (CMJ HOH , p < 0.001; CMJ HOHwatts , p = 0.003) as well as sophomore to senior (CMJ HOH , p < 0.001; CMJ HOHwatts , p = 0.02). Countermovement vertical jump with hands on hips also increased from sophomore to junior ( p = 0.005). The lower FFM and power capabilities as freshmen compared with upperclassman indicate a potential limited readiness. Coaches and training staff should account for these developmental differences when entering the preseason. Adequate conditioning programs before starting a collegiate program may help build a fitness foundation and prepare freshmen athletes to compete at the same level as their upperclassmen counterparts.

Psychological and Physiological Changes in Response to the Cumulative Demands of a Women's Division I Collegiate Soccer Season.

ABSTRACT: McFadden, BA, Walker, AJ, Bozzini, BN, Hofacker, M, Russell, M, and Arent, SM. Psychological and physiological changes in response to the cumulative demands of a women's division I collegiate soccer season. J Strength Cond Res 36(5): 1373-1382, 2022-This study sought to determine the effects of a women's collegiate soccer season on psychological markers, biomarkers, sleep, and performance. Athletes participated in maximal countermovement vertical jump height (CMJ) assessments and biomarker monitoring in conjunction with subjective measures of psychological wellness and sleep questionnaires before preseason (S1) and every 4 weeks following (S2, S3, and S4). Training was monitored during practices and games using global positioning satellite systems and heart rate technology. Total training load was highest from S1 to S2, decreased from S2 to S3 (effect size [ES] = -2.5; p < 0.001), and remained stable from S3 to S4. CMJ declined at S2 (ES1-2 = -0.51; p = 0.001) and returned to baseline at S3. Increases from S1 to S2 were seen for creatine kinase (ES1-2 = 1.74), free testosterone (ES1-2 = 1.27), total testosterone (ES1-2 = 3.5), and free cortisol (ES1-2 = 0.88) (p < 0.03) before returning to baseline by S3 and S4 (free cortisol). Total cortisol was elevated throughout the season before declining at S4 (ES1-4 = -0.41; p = 0.03). Iron declined from S1 to S2 (ES1-2 = -0.73; p = 0.01) and returned to baseline values at S4, whereas growth hormone declined at S2 (ES1-2 = -0.50; p = 0.01) and remained depressed. Interleukin-6 increased at S4 (ES1-4 = 0.71; p = 0.02). Total training distress decreased from S1 to S2 (ES1-2 = -0.38; p = 0.02), returned to baseline by S3, and increased by S4 (ES1-4 = 0.57; p = 0.01). No changes were observed in markers of sleep (p > 0.05). Biomarkers showed notable changes after the highest workload period (S1-S2), which coincided with CMJ decrements. Biomarker perturbations preceded declines in subjective psychological wellness (S4) which occurred in the latter half of the season, indicating an accumulation of fatigue as the season progressed.

Evaluation of Performance Characteristics and Internal and External Training Loads in Female Collegiate Beach Volleyball Players.

ABSTRACT: Bozzini, BN, McFadden, BA, Scruggs, SK, and Arent, SM. Evaluation of performance characteristics and internal and external training loads in female collegiate beach volleyball players. J Strength Cond Res 35(6): 1559-1567, 2021-Although women's beach volleyball is the fastest growing collegiate sport, the training demands and performance characteristics have yet to be determined. The purpose of this study was to evaluate internal and external training loads throughout a competitive season and to quantify the performance characteristics of National Collegiate Athletic Association Division I women's beach volleyball players. Female beach volleyball players (N = 20) were monitored throughout the 6-week competitive season (T1-T6) using integrative global positioning systems (GPS) and heart rate (HR)-monitoring technology, which was individualized based on preseason testing, for the determination of workload metrics. In addition to team data, all variables were analyzed between travel (n = 11, regular match participation) and non-travel (n = 7) squad athletes (p < 0.05). Team performance metrics demonstrated the explosive power emphasis of the sport, with travel squad players exhibiting significantly greater vertical jump and jump velocity abilities than their non-travel counterparts (p < 0.05). Although few time main effects from T1 to T6 were observed for team workload metrics, follow-ups revealed significant time × group interactions for training load (TL), exercise energy expenditure (EEE), total distance covered, and minutes spent in HR zones (HRZ1-Z5) over the season (p < 0.05). Finally, although average workloads were greater in practices than in matches, when accounting for pre-match warm-ups, competition load was greater than practice (p < 0.05). National Collegiate Athletic Association Division I women's beach volleyball is a demanding, explosive power sport characterized by overall large TL and EEE, particularly in-season when athletes compete in 4 matches per weekend. The workloads observed point to the need to assess and manage training loads and fueling requirements to optimize performance and decrease injury risk.

Training Demands and Physiological Profile of Cross-Disciplined Collegiate Female Dancers.

ABSTRACT: Sanders, DJ, Walker, AJ, Prior, KE, Poyssick, AN, and Arent, SM. Training demands and physiological profile of cross-disciplined collegiate female dancers. J Strength Cond Res 35(8): 2316-2320, 2021-Little is known about the physical demands of high-level dance training. Therefore, the purpose of this study was to investigate the physiological demands of a typical ballet and modern class through training load (TL) and to assess differences in TL between the 2 class types. In addition, a physiological profile of cross-disciplined collegiate female dancers was determined. Seventeen college-aged female dancers were recruited and performed a battery of performance tests assessing body fat (%BF), lean body mass, vertical jump (VJ), peak power, maximal oxygen consumption (V̇o2max), and ventilatory threshold (VT). Two ballet and modern dance classes were monitored for TL and exercise energy expenditure (EEE) using the Polar Team2 Pro System. Performance testing results were as follows: M%BF = 24.1 ± 4.2%, MLBM = 46.8 ± 8.5 kg, MV̇o2max = 42.9 ± 4.3 ml·kg-1·min-1, MVT = 76.2 ± 6.5% of V̇o2max, MVJ = 44.1 ± 1.4 cm, and MPP = 519.1 ± 177.5 W. Training load of 41.0 ± 17.0 for ballet and 44.8 ± 27.4 for modern dance was found, with an EEE of 394.0 ± 111.9 and 421.9 ± 161.4 kcal, respectively. Time spent at or above VT was 1.2 ± 2.6 minutes in ballet and 3.4 ± 8.3 minutes in modern. Compared with other female power-endurance athletes, the dancers accumulated a much lower TL during both class types. Low TL may inhibit typical adaptations seen in other athletes, which may explain why dancers in this study had lower aerobic and anaerobic capacities and higher body fat percentage than other collegiate female athletes. Also, it suggests that supplemental conditioning could be incorporated into a dancers training paradigm to optimize performance.

The Relationships Between Perceived Wellness, Sleep, and Acute: Chronic Training Load in National Collegiate Athletics Association Division I Male Soccer Players.

ABSTRACT: Sekiguchi, Y, Curtis, RM, Huggins, RA, Benjamin, CL, Walker, AJ, Arent, SM, Adams, WM, Anderson, T, and Casa, DJ. The relationships between perceived wellness of, sleep of, and acute: chronic training load on National Collegiate Athletics Association division I male soccer players. J Strength Cond Res 35(5): 1326-1330, 2021-The purpose of this study was to investigate relationships between perceived wellness, sleep, and acute: chronic workload ratio (ACWR) throughout a collegiate men's soccer season. Sixty male collegiate soccer players (mean[M] ± SD; age, 21±2 year; body mass, 77.6 ± 6.5 kg; height, 180.1 ± 6.4 cm; body fat%, 9.9 ± 3.9% ; and V̇o2max, 53.1 ± 5.0 ml·kg-1·min-1) participated in this study. During each session, players used a heart rate and global positioning satellite-enabled chest strap to measure training impulse and ACWR. The ACWR values were trichotomized at the individual level giving an equal number of observations within each ACWR category of low, moderate, and high ACWR (M ± SD; low, 0.658 ± 0.23; moderate, 0.92 ± 0.15; and high, 1.17 ± 0.16). Stress, fatigue, and soreness levels were collected using 1-10 Likert scales and sleep duration, and sleep quality were measured by the Karolinska Sleep Diary. Stress, fatigue, soreness levels, and sleep quality were transformed to corresponding z-scores at the individual level. Fatigue levels were significantly higher when ACWR was high compared with low (mean difference [95% confidence intervals], effect size, p-value; 0.31 [0.21, 0.42], 0.29, p < 0.001) and moderate (0.14 [0.03, 0.24], 0.13, p = 0.01). Fatigue levels were also significantly higher when the ACWR was moderate compared with low (0.18 [0.07, 0.28], 0.16, p = 0.001). Soreness levels were significantly higher when the ACWR was high compared with low (0.25 [0.14, 0.36], 0.23, p < 0.001). Stress levels were significantly greater when the ACWR was high compared with low (0.19, [0.08, 0.29], 0.18, p < 0.001) and compared with moderate (0.15, [0.05, 0.25], 0.14, p = 0.004). There were no differences in sleep duration or sleep quality in different ACWR. The ACWR may be a useful tool to achieve an appropriate balance between training and recovery to manage daily fatigue and soreness levels in athletes.

Varying Demands and Quality of Play Between In-Conference and Out-of-Conference Games in Division I Collegiate Women's Soccer.

Bozzini, BN, McFadden, BA, Walker, AJ, and Arent, SM. Varying demands and quality of play between in-conference and out-of-conference games in Division I collegiate women's soccer. J Strength Cond Res 34(12): 3364-3368, 2020-The purpose of this study was to assess differences in physical workloads, physiological responses, and performance variables between in-conference (IC) and out-of-conference (OC) games during a collegiate women's soccer season. Female field players (N = 11), who played a minimum of 45 minutes for >50% of games, were evaluated using an integrative GPS and HR monitoring system to determine training load (TL), exercise energy expenditure (EEE), total distance covered (DIS), sprints, time spent in HR zones 4 and 5 (HRZ4 = 80-89% HRmax; HRZ5 = 90-100% HRmax), and distance covered in speed zones 4 and 5 (DISZ4 = 15.0-19.9 km·h; DISZ5 = ≥20 km·h). In addition, percent passing accuracy (PA%), dribbling success (DS%), tackling success (TS%), and challenges won (CW%) were generated for all games. Workload data were analyzed as a rate per minute playing time (PT) per game to account for differences in game duration and PT between OC (n = 7) and IC games (n = 11). Repeated-measures multivariate analyses of variance with univariate follow-ups and effect sizes (Hedges' g) were conducted to compare conditions (OC vs. CON) (p < 0.05). There were significantly greater TL, DIS, EEE, and HRZ5 per minute PT in OC versus IC games (Hedges' g: TL = 0.48; DIS = 0.20, EEE = 0.55; HRZ5 = 0.83; p < 0.05). Further analysis found significant differences in first half play favoring OC games (p < 0.05), but not second half play (p > 0.05). Based on these findings, OC games seem to be more demanding compared to IC, particularly during first half play. Emphasis should be placed on tailoring TL to the accumulating in-season demands through athlete-monitoring technology to prevent declines in performance in the latter half of the season.

Comparison of Internal and External Training Loads in Male and Female Collegiate Soccer Players During Practices vs. Games.

McFadden, BA, Walker, AJ, Bozzini, BN, Sanders, DJ, and Arent, SM. Comparison of internal and external training loads in male and female collegiate soccer players during practices vs. games. J Strength Cond Res 34(4): 969-974, 2020-The purpose of this study was to compare the internal and external training loads (TLs) in men and women throughout a Division I soccer season during practices versus games. Players were evaluated during all practices and regulation game play using the Polar TeamPro system, utilizing Global Positioning Satellite technology and heart rate (HR) monitoring to determine TL, time spent in HR zones expressed as a percent of HRmax (HRZ1-Z5), calories expended per kilogram body mass (Kcal·kg), distance covered (DIS), sprints, average speed (SPDAVG), and distance covered in speed zones (DISZ1-Z5). During games, no significant differences were seen between men and women for TL, Kcal·kg, HRZ1-Z5, SPDAVG, DIS, DISZ1, DISZ3, and DISZ4. However, men accumulated a significantly greater number of sprints and DISZ5 (p < 0.05) during games, whereas women accumulated a greater DISZ2 (p < 0.05). During practice, no differences were observed for TL, DIS, sprints, Kcal·kg, DISZ2, DISZ3, HRZ1-Z5, but men exhibited higher SPDAVG, (p < 0.05), DISZ1 (p < 0.05), DISZ4 (p < 0.05), and DISZ5 (p < 0.05). The parallels in Kcal·kg, total DIS, HR, and TL indicate a similar relative workload between men and women. However, distance covered in higher speed zones was found to be greater in men than women across practice and games likely reflecting inherent sex differences in the ability to achieve those speeds. Monitoring techniques that track relative player workloads throughout practices and games may enhance player health and performance during the season. An individualized approach to tracking high-intensity running may improve workload prescriptions on a per player basis.

Early Season Hormonal and Biochemical Changes in Division I Field Hockey Players: Is Fitness Protective?

Walker, AJ, McFadden, BA, Sanders, DJ, Bozzini, BN, Conway, SP, and Arent, SM. Early season hormonal and biochemical changes in Division I field hockey players: is fitness protective? J Strength Cond Res 34(4): 975-981, 2020-The purpose was to evaluate changes in hormonal and biochemical markers as a result of the accumulated stress of the initial 4-week training block in field hockey players. Women's Division I field hockey players (N = 22; Mage = 19.7 ± 1.1 years) performed testing before the start of preseason (A1) that included body composition (%BF), vertical jump, and V[Combining Dot Above]O2max. Blood draws were conducted at A1 to assess creatine kinase (CK), iron (Fe), hemoglobin (HGB), hematocrit (HCT), percent saturation (%sat), total cortisol (TCORT), free cortisol (FCORT), interleukin-6 (IL-6), sex hormone-binding globulin (SHBG), prolactin (PRL), vitamin D (vitD), and thyroxine (T3). Blood draws were repeated 4 weeks later (A2). Athletes were monitored during this training block, which included 2 weeks of preseason and the first 2 weeks of the season, using heart rate monitors to determine energy expenditure (Kcal) and training load. There were significant disruptions in TCORT, FCORT, T3, CK, Fe, and SHBG (p < 0.05) from A1 to A2. V[Combining Dot Above]O2max accounted for 31% (p < 0.05) of the variance in TCORT and %BF accounting for an additional 20.1% (p < 0.05). V[Combining Dot Above]O2max accounted for 32.7% (p < 0.05) of the variance in FCORT. %BF accounted for 48.9% (p < 0.05) of the variance in T3. Kcal was positively correlated with V[Combining Dot Above]O2max (p < 0.05) and negatively correlated with %BF (p < 0.05). Athletes with higher V[Combining Dot Above]O2max and lower %BF may be capable of a higher work output and therefore more likely to experience increased physiological disruptions during intense training. The high-volume nature of preseason and differences in athlete fitness capabilities require coaches to manage players at an individual level to maintain athlete readiness.

Contextual Factors Influencing External and Internal Training Loads in Collegiate Men's Soccer.

Curtis, RM, Huggins, RA, Benjamin, CL, Sekiguchi, Y, Adams, WM, Arent, SM, Jain, R, Miller, SJ, Walker, AJ, and Casa, DJ. Contextual factors influencing external and internal training loads in collegiate men's soccer. J Strength Cond Res 34(2): 374-381, 2020-This study investigated factors influencing training loads (TL) in collegiate men's soccer. Total distance, high-speed running distance (>14.4 km·h), high-intensity heart-rate zone duration (HI HRZ, >70% heart rate relative to maximum), and session rating of perceived exertion were assessed daily from 107 male soccer players competing for 5 National Collegiate Athletics Association Division I teams. Differences between athlete role (starter and reserve), position (defender, midfielder, and forward), season phase (preseason, in-season, and postseason), days relative to match (MD-1 to MD-5+), days between matches (<4, 4-5, >5 days), previous match outcome (win, loss, and draw), and upcoming opponent relative ranking (weaker, trivial, and stronger) were examined. Mean differences (MD) and effect sizes (ESs) with 90% confidence intervals were reported. There were trivial and insignificant differences by player role, position, or upcoming opponent strength, and small-moderate increases in preseason TL compared with in-season (ES [range] = 0.4-0.9). TLs were lower for MD-1 and higher for MD-5+ (ES [range] = 0.4-1.3) when compared with MD-2-4. External loads (ES = -0.40 ± 0.20) were less after wins compared with losses. TLs are increased in the preseason, when training sessions occur greater than 5 days from a match and after losses. Contextualizing factors affecting TLs has implications for developing workload prescription and recovery strategies.

Anticipatory Salivary Cortisol and State Anxiety Before Competition Predict Match Outcome in Division I Collegiate Wrestlers.

Cintineo, HP and Arent, SM. Anticipatory salivary cortisol and state anxiety before competition predict match outcome in Division I collegiate wrestlers. J Strength Cond Res 33(11): 2905-2908, 2019-Anticipation of exercise and other stressors has been shown to result in physiological and psychological changes, which include increased levels of cortisol and anxiety. Combat sports, in particular, typically elicit robust anticipatory responses because of the distinct nature of these sports. Therefore, the purpose of this investigation was to examine the relationship between state anxiety scores, anticipatory cortisol response, and performance outcomes in college wrestlers. A secondary purpose was to determine the correlation between anticipatory cortisol and state anxiety scores. Twenty-six collegiate wrestlers were recruited to undergo saliva collection and to complete the State Anxiety Inventory before a wrestling match and again on a rest day in a time-matched, control session. Univariate analyses revealed that both salivary cortisol and anxiety were greater before competition than on a rest day. In addition, it was found that losers had higher levels of anticipatory cortisol and anxiety compared with winners. A significant correlation between salivary cortisol and anxiety was found as well. These data show that higher cortisol and anxiety may negatively affect performance. Athletes and coaches should work together to determine optimal levels of arousal and should aim to replicate this during both training and competition to ensure consistently high levels of performance through appropriate preparation.

Biomarker Response to a Competitive Season in Division I Female Soccer Players.

Walker, AJ, McFadden, BA, Sanders, DJ, Rabideau, MM, Hofacker, ML, and Arent, SM. Biomarker response to a competitive season in Division I female soccer players. J Strength Cond Res 33(10): 2622-2628, 2019-The purpose of this study was to evaluate effects of training load (TL) on performance and biomarkers of health, performance, and recovery in Division I female soccer players throughout a competitive season. Subjects (N = 25, Mage = 20 ± 1.1 years) were monitored before the start of preseason and every 4-weeks thereafter (T1-T5). A battery of performance tests was administered before the start of preseason (P1) and end-of-season (P2), including body composition (percent body fat [%BF], fat free mass [FFM], and fat mass), vertical jump (VJ), and VO2max. Blood draws were conducted at every time point (T1-T5) to assess free and total cortisol (CORTF and CORTT), prolactin (PRL), T3, IL-6, creatine kinase (CK), sex-hormone binding globulin, omega-3 (n-3FA), vitamin-D (Vit-D), iron (Fe), hematocrit (HcT), ferritin (Fer), percent saturation (%Sat), and total iron-binding capacity (TIBC). Daily exercise energy expenditure (EEE) and TL were determined. There were significant declines in VO2max, VJ, weight, and %BF from P1-P2 (p < 0.05) with no significant differences in FFM. Training load and EEE significantly decreased from T1-T3 (p < 0.05). Significant increases were seen in CORTT, CORTF, PRL, T3, IL-6, CK, and TIBC throughout the season (p < 0.05). Significant decreases were seen in n-3FA, Fe, Fer, %Sat, and Hct throughout the season (p < 0.05). Female athletes experience significant physiological changes following high TL and EEE associated with preseason and appear to be further exacerbated by the cumulative effects of the season. Unique insights provided by biomarkers enable athletes and coaches to be cognizant of the physiological changes that are occurring throughout the season.

The Combined Effects of Exercise, Diet, and a Multi-Ingredient Dietary Supplement on Body Composition and Adipokine Changes in Overweight Adults.

BACKGROUND: Very few weight and fat loss supplements undergo finished-product research to examine efficacy. The purpose of this study was to determine the effects of an 8-week diet and exercise program on body composition, hip and waist girth, and adipokines and evaluate whether a dietary supplement containing raspberry ketone, capsaicin, caffeine, garlic, and Citrus aurantium enhanced outcomes. METHODS: Overweight men and women completed this randomized, placebo-controlled, double-blind study. Participants consumed 4 capsules/d of supplement (EXP; n = 18) or placebo (PLA; n = 18). Participants underwent 8 weeks of daily supplementation, calorie restriction (500 kcal < RMR [resting metabolic rate] × 1.2), and supervised progressive exercise training 3 times a week. Body composition, girth, and adipokines were assessed at baseline and postintervention (T1 and T2). RESULTS: Significant decreases in weight (-2.6 ± 0.57 kg, p < 0.001), fat mass (-1.8 ± 0.20 kg; p < 0.001), and percentage body fat (-3.7% ± 0.29%, p < 0.001) and a significant increase in lean body mass (LBM; 1.5 ± 0.26 kg; p < 0.001) were seen from T1 to T2 in both groups. For men, only those in the EXP group increased LBM from T1 to T2 (1.3 ± 0.38 kg; p < 0.05). Hip girth was also reduced, with the women in the EXP group (-10.7 ± 2.15 cm, p < 0.001) having a greater reduction. There was a time by group interaction, with significant decreases in leptin (p < 0.001) and significant increases in adiponectin (p < 0.05) in the EXP group. CONCLUSIONS: Significant improvements in adipokines and leptin support the utility of exercise, diet, and fat loss for impacting inflammatory biomarkers. The improvement in adiponectin with EXP may suggest a unique health mechanism.

Acute Physiological Responses to an Intensity-And Time-Under-Tension-Equated Single- vs. Multiple-Set Resistance Training Bout in Trained Men.

Cintineo, HP, Freidenreich, DJ, Blaine, CM, Cardaci, TD, Pellegrino, JK, and Arent, SM. Acute physiological responses to an intensity-and time under-under-tension-equated single- vs. multiple-set resistance training bout in trained men. J Strength Cond Res 32(12): 3310-3318, 2018-Regardless of the setting, proper manipulation of resistance training program design variables is pivotal in eliciting the desired physiological adaptations. Furthermore, how these variables, especially volume and intensity, work together to affect training outcomes is a major topic of investigation. The purpose of this study was to compare the acute biochemical, physiological, and hormonal responses of a single-set accentuated eccentric high-intensity training (HIT) protocol to a traditional 3-set protocol to better understand the acute effects of volume. Resistance-trained male college students (N = 19; age = 21.11 ± 2.5 years; height = 174.33 ± 6.83 cm; body mass = 76.72 ± 10.24 kg; %BF = 15.53 ± 6.35%) participated in this study and were randomly assigned to either the 1-set HIT protocol (HIT) or the 3-set traditional (3ST) protocol. Heart rate (HR), blood lactate, salivary testosterone, and salivary cortisol levels were measured before, during, and at multiple time points after the exercise bout. Results showed no differences in average HR or testosterone at any time point between the 2 groups. However, the 3ST group exhibited higher values of peak HR, blood lactate during exercise, and cortisol during and 30 minutes after exercise than the HIT group. This indicated that the 3ST protocol induced greater metabolic stress and disrupted the homeostatic balance to a greater magnitude than the HIT protocol despite similar time under tension. These results show that even when training to momentary muscular failure, volume seems to be a key driver of the training stimulus.

Measurement of Cortisol and Testosterone in Athletes: Accuracy of Liquid Chromatography-Tandem Mass Spectrometry Assays for Cortisol and Testosterone Measurement in Whole-Blood Microspecimens.

Fragala, MS, Goldman, SM, Goldman, MM, Bi, C, Colletti, JD, Arent, SM, Walker, AJ, and Clarke, NJ. Measurement of cortisol and testosterone in athletes: Accuracy of LC-MS/MS assays for cortisol and testosterone measurement in whole-blood microspecimens. J Strength Cond Res 32(9): 2425-2434, 2018-Biomarker monitoring provides insight into athletes' training tolerance but is limited by the need for office-based specimen collection. To facilitate self-collection during training, we developed liquid chromatography-tandem mass spectrometry-based tests that measure circulating total cortisol and testosterone using a finger stick volumetric absorptive microsampler. Here, we describe the analytical validation of these tests. Forty-six Division I athletes (18-22 years, 30 women, 16 men) provided a 20-µL finger stick microspecimen and a 5-ml venous blood specimen from the forearm; the venous blood sample was analyzed using both normal volume serum analysis and analysis of dried whole blood (from the microsampler). Liquid chromatography-tandem mass spectrometry on standard serum specimens obtained by venipuncture yielded total cortisol levels of 26.2 ± 11.6 µg·dl (women and men), and total testosterone levels of 37 ± 17 ng·dl in women and 564 ± 171 ng·dl in men. Analytical measurement ranges of the microspecimen assay were 0.3-440 µg·dl (CV <9%) for cortisol and 15 to 20,000 ng·dl (CV <9%) for testosterone. Deming regression and Pearson correlation indicated good test accuracy for the microspecimen tests compared with venipuncture tests for cortisol (y = 0.98x + 1.34, 95% CI of slope = 0.83-1.14; r = 0.92, p < 0.0001) and testosterone (y = 1.06x - 0.01, 95% CI of slope = 0.99-1.14; r = 0.99, p < 0.0001). Similarly, high agreement was observed between finger stick and venous microspecimens for cortisol (y = 1.00x + 0.65, 95% CI of slope = 0.9-1.11; r = 0.96, p < 0.001) and testosterone (y = 0.97x + 2.75, 95% CI of slope = 0.9-1.03; r = 0.99, p < 0.001). These findings suggest the viability of finger stick collection whole-blood microspecimens for assessment of total cortisol and testosterone in athletes.

The Effects of Caffeine on Arousal, Response Time, Accuracy, and Performance in Division I Collegiate Fencers.

Doyle, TP, Lutz, RS, Pellegrino, JK, Sanders, DJ, and Arent, SM. The effects of caffeine on arousal, response time, accuracy, and performance in Division I collegiate fencers. J Strength Cond Res 30(11): 3228-3235, 2016-Caffeine has displayed ergogenic effects on aerobic performance. However, sports requiring precision and quick reaction may also be impacted by central nervous system arousal because of caffeine consumption. The purpose of this study was to assess the effects of caffeine on arousal, response time (RT), and accuracy during a simulated fencing practice. Using a randomized, within-subjects, placebo-controlled, double-blind design, Division I male and female college fencers (N = 13; 69.1 ± 3.5 kg) were administered caffeine doses of 0, 1.5, 3.0, 4.5, 6.0, or 7.5 mg·kg during separate testing days. Performance was assessed via RT and accuracy to a 4-choice reaction task. A total of 25 trials were performed each day using a random 2- to 8-s delay between trials. Arousal was assessed using the activation-deactivation adjective check list. Results of repeated-measures multivariate analysis of variance revealed a significant dose effect (p = 0.02) on performance. Follow-up analyses indicated this was due to a significant effect for RT (p = 0.03), with the dose-response curve exhibiting a quadratic relationship. Response time was significantly faster (p < 0.01) for the 1.5, 3.0, and 6.0 mg·kg conditions than for the placebo condition. Results also indicated a significant dose effect for composite RT + accuracy performance (p < 0.01). The dose-response curve was again quadratic, with performance beginning to deteriorate at 7.5 mg·kg. Energetic arousal, tiredness, tension, and calmness all significantly changed as a function of caffeine dose (p ≤ 0.05). Based on these results, caffeine improves RT and overall performance in fencers, particularly as doses increase up to 4.5-6.0 mg·kg. Above this level, performance begins to deteriorate, consistent with an "inverted-U" model of arousal and performance.

Effects of over-the-counter jaw-repositioning mouth guards on dynamic balance, flexibility, agility, strength, and power in college-aged male athletes.

Improvements in muscular power and anaerobic performance have resulted from the use of jaw-repositioning mouth guards designed with advanced dental techniques. The high cost of such techniques has dissuaded the widespread use. Recently, more affordable, over-the-counter (OTC) jaw-repositioning mouth guards have become available. The primary objective of this study was to examine the effects of 2 OTC jaw-repositioning mouth guards on muscular power and strength performance in college-aged male athletes. It was hypothesized that similar to previous observations with advanced dentistry-designed mouth guards, OTC jaw-repositioning mouth guards would impart positive effects on muscular power but not have any effect on muscular strength. Secondary objectives of this study included the examination of the effects of 2 OTC jaw-repositioning mouth guards on other variables related to athletic performance. Male collegiate athletes (N = 20) participated in 4 separate testing sessions that consisted of assessment of muscular power, dynamic balance, flexibility, agility, and muscular strength. The 4 conditions, 1 per testing session, were assigned in a randomized order and consisted of a no-mouth guard control (CON), a placebo mouth guard, a self-adapted jaw-repositioning mouth guard (SA), and a custom-fitted jaw-repositioning mouth guard (CF). No significant differences were observed between conditions in muscular power (p = 0.78), dynamic balance (p = 0.99), agility (p = 0.22), or muscular strength (p = 0.47). The CF had significantly lower hip flexion than the CON (p = 0.014) and had significantly greater lumbar spine lateral flexion compared with the SA condition (p = 0.054). However, these flexibility differences lack practical relevance as the effect sizes remain very small (ES = -0.27 and -0.14, respectively). In conclusion, the jaw-repositioning technique used in the design of these OTC mouth guards did not affect performance. It is important to note that negative effects were not observed indicating that mouth guard use did not impede performance.

The effects of a combined resistance training and endurance exercise program in inactive college female subjects: does order matter?

Although both endurance (E) and resistance (R) exercise improve various health and fitness variables, there is still debate regarding the optimal ordering of these modes of exercise within a concurrent bout. The purpose of this study was to determine the effects of performing E before R (E-R) or R before E (R-E) on strength, VO2max, and body composition over the course of an 8-week exercise program. Inactive college female subjects (N = 23; 19.8 ± 0.22 years; 61.0 ± 2.5 kg) were randomly assigned to either an E-R (n = 13) or an R-E (n = 10) group. Subjects trained 4 d·wk over the 8-week study. The E portion consisted of 30 minutes of aerobic exercise at 70-80% heart rate reserve (HRR). The R portion used a 3-way split routine with subjects performing 3 sets of 8-12 repetitions for 5-6 different exercises using a load equal to 90-100% 10 repetition maximum. There were 2 days of testing before and after 8 weeks of training to determine performance and body composition. There were significant improvements in chest press (p < 0.001), leg press (p < 0.001), VO2max (p < 0.001), and lean body mass (LBM) (p = 0.005) across both groups. Weight significantly increased (p = 0.038), but percent body fat did not change (p = 0.46). There were no differences as a function of group (p > 0.267). There were significant improvements in performance and LBM over an 8-week concurrent training program in inactive college female subjects, regardless of the order in which R and E were performed. It seems that fitness markers improve similarly regardless of the order of R or E in a 4 d·wk-1 program in inactive female subjects. Therefore, the order of these modalities for beginning exercisers should be based on personal preference and to facilitate adherence.

Unsupervised Machine Learning in Countermovement Jump and Isometric Mid-Thigh Pull Performance Produces Distinct Combat and Physical Fitness Clusters in Male and Female U.S. Marine Corps Recruits.

INTRODUCTION: Several challenges face the U.S. Marine Corps (USMC) and other services in their efforts to design recruit training to augment warfighter mobility and resilience in both male and female recruits as part of an integrated model. Strength and power underpin many of the physical competencies required to meet the occupational demands one might face in military. As the military considers adopting force plate technology to assess indices of strength and power, an opportunity presents itself for the use of machine learning on large datasets to deduce the relevance of variables related to performance and injury risk. The primary aim of this study was to determine whether cluster analysis on baseline strength and power data derived from countermovement jump (CMJ) and isometric mid-thigh pull (IMTP) adequately partitions men and women entering recruit training into distinct performance clusters. The secondary aim of this study is then to assess the between-cluster frequencies of musculoskeletal injury (MSKI). MATERIALS AND METHODS: Five hundred and sixty-five males (n = 386) and females (n = 179) at the Marine Corps Recruit Depots located at Parris Island and San Diego were enrolled in the study. Recruits performed CMJ and IMTP tests at the onset of training. Injury data were collected via medical chart review. Combat fitness test (CFT) and physical fitness test (PFT) results were provided to the study team by the USMC. A k-means cluster analysis was performed on CMJ relative peak power, IMTP relative peak force, and dynamic strength index. Independent sample t-tests and Cohen's d effect sizes assessed between-cluster differences in CFT and PFT performance. Differences in cumulative incidence of lower extremity %MSKIs were analyzed using Fisher's exact test. Relative risk and 95% confidence intervals (CIs) were also calculated. RESULTS: The overall effects of cluster designation on CMJ and IMTP outcomes ranged from moderate (relative peak power: d = -0.68, 95% CI, -0.85 to -0.51) to large (relative peak force: d = -1.69, 95% CI, -1.88 to -1.49; dynamic strength index: d = 1.20, 95% CI, 1.02-1.38), indicating acceptable k-means cluster partitioning. Independent sample t-tests revealed that both men and women in cluster 2 (C2) significantly outperformed those in cluster 1 (C1) in all events of the CFT and PFT (P < .05). The overall and within-gender effect of cluster designation on both CFT and PFT performance ranged from small (d > 0.2) to moderate (d > 0.5). Men in C2, the high-performing cluster, demonstrated a significantly lower incidence of ankle MSKI (P = .04, RR = 0.2, 95% CI, 0.1-1.0). No other between-cluster differences in MSKI were statistically significant. CONCLUSIONS: Our results indicate that strength and power metrics derived from force plate tests effectively partition USMC male and female recruits into distinct performance clusters with relevance to tactical and physical fitness using k-means clustering. These data support the potential for expanded use of force plates in assessing readiness in a cohort of men and women entering USMC recruit training. The ability to pre-emptively identify high and low performers in the CFT and PFT can aid in leadership developing frameworks for tailoring training to enhance combat and physical fitness with benchmark values of strength and power.