Jones, Margaret T.

Abstract Burke, AA, Saine, ND, King, EL, Fields, JB, Jagim, AR, Miller, AD, Green, BC, and Jones, MT. Longitudinal modeling of pitching workload and countermovement jump performance as determinants of fastball velocity and consistency in collegiate baseball pitchers. J Strength Cond Res XX(X): 000–000, 2026—Maintenance of four-seam fastball (FSFB) velocity across the baseball season is critical, yet the extent to which workload and neuromuscular status relate to velocity is unclear. Thus, aims of the current study were to assess the relationship between external pitching workload metrics and FSFB velocity; quantify within-season FSFB velocity; and examine how countermovement jump (CMJ) performance predicts FSFB velocity. Collegiate pitchers ( n = 8) completed weekly CMJ testing during a 15-week, 53-game season. Countermovement jump metrics included jump height (JH), reactive strength index–modified (RSImod), peak braking force, and peak propulsive force normalized to body mass. Workload variables (innings, total pitches, FSFB pitches) and FSFB velocity were evaluated via repeated measures correlation (RMCORR). A longitudinal heat map visualized velocity trends, and a hierarchical location–scale model assessed predictors of mean velocity and variance. Repeated measures correlation showed weak negative associations between FSFB velocity and innings ( r = −0.15, p = 0.11), total pitches ( r = −0.18, p = 0.05), and FSFB pitches ( r = −0.18, p = 0.05). Heat map analysis identified 3 distinct velocity clusters. Location model results indicated no predictors of mean velocity. The scale model showed JH ( γ = −0.060, p = 0.001) predicted reduced velocity variance, and RSImod ( γ = 3.800, p < 0.001) predicted increased variance. Findings suggest that velocity patterns varied across athletes, where greater workloads were negatively associated with FSFB pitch velocity. Further, CMJ performance related to velocity stability rather than mean velocity. Routine longitudinal monitoring and continued strength-power training are recommended to support FSFB velocity.

The primary aim of this study was to examine pitching performance metrics before and after ulnar collateral ligament reconstruction (UCLR) among Major League Baseball (MLB) starting and relief pitchers. The following information was extracted from the “Tommy John Surgery List” database regarding UCLR surgeries among MLB pitchers: UCLR date, pitcher type (starting pitcher, relief pitcher), and age at time of UCLR. Pitching performance metrics were extracted from the Baseball Savant online platform for the two seasons immediately prior to UCLR (pre) and the two seasons immediately following returning to pitching after UCLR (post). Fifty-nine pitchers were included in this study (29 starting pitchers, 30 relief pitchers). The outcome measures included the number of pitches thrown, earned run average (ERA), walks plus hits per inning pitched (WHIP), strikeout percentage, whiff percentage, walk percentage, batting average against, ground ball percentage, and fastball velocity. There was a pitcher type-by-time interaction effect for ERA (p = 0.01; η2 = 0.12) and WHIP (p = 0.01; η2 = 0.12). Starting pitcher ERA increased from 3.68 to 4.40 from pre- to post-surgery, while relief pitcher ERA decreased from 4.47 to 3.90. In addition, starting pitcher WHIP increased from 1.22 to 1.29 from pre- to post-surgery, while relief pitcher WHIP decreased from 1.38 to 1.28. There was a main effect of time for pitches thrown (p = 0.04; η2 = 0.07). Significant differences between starting and relief pitchers were observed for changes in ERA and WHIP following UCLR, whereas no pitcher type-by-time interactions were observed for the remaining performance metrics. Both starting and relief pitchers threw fewer pitches following UCLR, while fastball velocity and other key pitching performance metrics remained largely unchanged.

Objective: To evaluate the current literature on the role of collagen peptide supplementation in bone health, focusing on changes in bone turnover markers (BTMs) and bone mineral density (BMD). Data Sources: A search was conducted following PRISMA guidelines in the databases Academic Search Premier, APA PsychInfo, CINAHL Plus, GreenFILE, MEDLINE, and SPORTDiscus. Keywords included “collagen supplementation,” “bone turnover,” and “bone structure.” Studies published between January 2000 and March 2024 were included if they involved human subjects, oral collagen supplementation, and skeletal-related outcomes (BTMs or BMD). Risk of bias was assessed using the modified Physiotherapy Evidence Database (PEDro) scale. Main Results: Fifteen studies met the inclusion criteria. Collagen supplementation was associated with improvements in BTMs such as procollagen type I N-terminal propeptide and C-terminal telopeptide of type I collagen, as well as increases in BMD at whole body, femoral neck, and lumbar spine sites, particularly in postmenopausal women. However, neutral findings and substantial heterogeneity in study design, population characteristics, and dosing protocols were also observed. Conclusions: Collagen supplementation shows promise for supporting bone health, particularly in postmenopausal women, but the evidence remains inconsistent. Future research should address these gaps by focusing on premenopausal populations, standardizing dosing protocols, and exploring broader orthopedic applications, such as reducing stress fractures and enhancing recovery from musculoskeletal injuries.

Background/Objectives: Women’s wrestling is one of the fastest growing sports within the United States at the high school and collegiate level. Weight-class sports, such as wrestling, present unique challenges for female athletes, particularly in managing acute weight fluctuations associated with the menstrual cycle. However, less is known regarding how sex-specific physiology may influence weight management strategies among female wrestlers. The purpose of this review was to highlight current weight loss trends among high school and collegiate female wrestlers and summarize the physiological mechanisms driving potential menstrual-related fluid retention and subsequent changes in body mass or composition. Methods: A literature review was conducted to include studies evaluating weight loss trends in female wrestlers competing in the United States. Additional literature focused on fluid, body mass, and body composition changes throughout the menstrual cycle was also included. Results: Recent evidence has provided observational data that can be used to develop descriptive summaries of current body composition profiles and weight loss trends among female wrestlers. These data can help to quantify the typical magnitude of weight loss changes observed in female wrestlers competing at the high school and collegiate level within the United States. Conclusions: These findings help provide insight into the magnitude of weight loss wrestlers undergo in an effort to compete in their minimal weight class, thus informing practitioners of potential health risks and helping guide optimal weight management efforts.

Abstract Jagim, AR, Dobbs, WC, Horswill, CA, Twohey, E, Fields, JB, and Jones, MT. Prevalence and magnitude weight loss among collegiate wrestlers. J Strength Cond Res 40(1): 90–97, 2026—The purpose of this study was to examine the percentage of wrestlers who compete in their minimal weight class (MWC), and the magnitude of weight loss. Data from the 2023–2024 collegiate season were retrospectively analyzed resulting in a sample of 9,638 collegiate male wrestlers from the National Association of Intercollegiate Athletics ( n = 1,904) and all 3 divisions of the National Collegiate Athletics Association ( n = 7,734). All wrestlers completed skinfold assessments for weight certification at the start of the competition season. The lowest recorded weight class (LRW) achieved by each wrestler during the season was also recorded and used to determine magnitude of weight loss. Out of the 4,605 (53.2%) of wrestlers who competed in their MWC, their average amount of weight loss was significantly higher than those who did not compete in their MWC (3.9 ± 2.5 vs. 3.2 ± 2.9 kg.; p < 0.001), yet they had an initial lower body fat percentage (12.7 ± 2.9 vs. 17.5 ± 4.8%; p < 0.001). At the time of weight certification, wrestlers weighed 8.1 ± 4.5 (95% confidence interval (CI): 8.0–8.2; effect size (ES) = 1.8) kg more than their minimal wrestling weight. The LRW was 3.6 ± 2.9 (95% CI: 3.6–3.7; ES = 1.2) kg lower than their weight at the time of weight certification. Given that slightly more than half of the male wrestlers competed in their MWC, coaches and sports practitioners should recognize that not all athletes follow the traditional assumption of cutting to the lowest possible weight class. Importantly, those who did achieve their MWC had lower initial body fat percentages, limiting the amount of weight they could safely lose. This underscores the need for individualized weight management strategies that consider body composition and health implications.

Background: Differences in total daily energy expenditure (TDEE) across sports, sex, and skill level support the need for sport- and athlete-specific energy intake recommendations. The purpose of the current review was to examine TDEE and related markers of energy expenditure across field-based team sports. A secondary aim was to evaluate physical activity levels (PAL), calculated as TDEE divided by resting metabolic rate (RMR), and their utility in estimating energy needs within team sports. Methods: The review was limited to studies that included the field-based team sports of rugby or soccer and reported energy expenditure data using doubly labeled water (DLW). A literature review identified 11 studies meeting criteria. Weighted means (Xw) and standard deviations (SDw) were calculated for each variable when pooled across each sport category. Results: Rugby (4417 ± 654 kcal·d−1) had a higher average TDEE than soccer (3157 ± 331 kcal/day; p < 0.001). When normalized to body mass, rTDEE was similar between sports (rugby: 49.5 ± 1.3 kcal·kg−1·day−1; soccer: 49.3 ± 1.8 kcal·kg−1·day−1; p = 0.967). PAL values were significantly higher in rugby (2.2 ± 0.4) compared to soccer (1.7 ± 0.2; p = 0.004). RMR was also greater in rugby (2136 ± 322 kcal·d−1) compared to soccer (1835 ± 208 kcal·d−1; p = 0.04). Conclusions: Rugby athletes exhibited higher TDEE values than soccer athletes, reflecting greater absolute energy demands. However, similar relative TDEE values suggest that differences in body size and composition likely contribute to the observed differences in absolute expenditure. These findings underscore the importance of individualized nutrition strategies within team sports and highlight PAL as a useful metric to contextualize energy requirements.

Abstract Fields, JB, Jones, MT, Kitts, SE, King, EL, and Jagim, AR. Relationships between disordered eating, body dissatisfaction, and low energy availability in women collegiate athletes. J Strength Cond Res 40(2): e164–e171, 2026—Women collegiate student-athletes face unique challenges regarding nutrition, body image, and athletic performance, increasing their risk for low energy availability (LEA), disordered eating (DE), and body dissatisfaction (BID). However, limited data exist exploring LEA, DE, and BID across a variety of women's sports. Therefore, the purpose of this study was to evaluate the prevalence of and relationships among LEA risk, DE behaviors, and BID in women collegiate athletes from multiple sports. Division I, II, and III women student-athletes ( n = 115) participated in this cross-sectional, descriptive study. Athletes completed the low energy availability for females questionnaire (LEAF-Q), eating attitudes test (EAT-26), muscularity-oriented eating test (MOET), and body dissatisfaction items from the eating disorder examination questionnaire (EDE-Q) to assess LEA risk, DE behaviors, and BID, respectively. Sixty-four percentages of athletes were at risk for LEA, with the highest prevalence in volleyball (100%), wrestling (68%), lacrosse (67%), and cross country (57%). However, only 8% of athletes were classified at risk for eating disorders. Notably, 81 and 84% of athletes reported body weight and shape dissatisfaction, respectively, which was strongly associated with disordered eating behaviors (EAT-26: r = 0.707; MOET: r = 0.723, p < 0.001). These results show a high prevalence of LEA risk and BID across athletes, with DE behaviors strongly linked to body image concerns. Despite a high LEA risk among athletes, clinical eating disorder risk remained low, suggesting that undereating may often be unintentional. Targeted interventions focused on nutritional education, body image, and psychological support are critical for improving health and performance outcomes among collegiate women student-athletes.

Abstract Twohey, E, Dobbs, WC, Malone, CM, Fields, JB, Jones, MT, and Jagim, AR. The use of a consumer-grade bioelectrical impedance analysis device for weight certification in collegiate wrestling: Implications for minimal wrestling weight determination. J Strength Cond Res 39(12): 1321–1326, 2025—Wrestlers are required to complete a preseason weight certification assessment, which includes a weigh-in, a hydration test, and a body fat percentage (BF%) measurement. This information is then used to establish their minimal wrestling weight (MWW) and minimal weight class. Skinfold (SKF) is the primary method used for determining body fat for collegiate wrestling, yet impedance devices are being considered for use in the future. The purpose of this study was to examine differences in body fat and the resulting MWW values derived from SKF and a consumer-grade multifrequency bioelectrical impedance analysis (MFBIA) device. Thirty-one collegiate male wrestlers produced a urine sample for urine specific gravity assessment to ensure adequate hydration status. Subjects then completed a weigh-in, followed by 2 body composition assessments using a (a) MFBIA device and (b) skinfold calipers to determine body density and BF%. No significant differences were observed for estimates of BF% (SKF: 13.4 ± 2.8% vs. MFBIA: 14.0 ± 3.3%; p = 0.198) or computed MWW values (SKF: 69.8 ± 8.7 kg vs. MFBIA: 69.4 ± 9.7 kg; p = 0.348) between devices. When determining the minimal weight class for each device, there were discrepancies in 11 of the 31 wrestlers (35%). Although the current MFBIA device can provide an acceptable estimate of BF% and similar resulting MWW value at the group level, the methods cannot be used interchangeably.

Abstract Korpinen, M, Magee, M, Dulak-Sigler, C, Fields, JB, Jagim, AR, King, E, Burke, A, and Jones, MT. Seasonal changes in neuromuscular performance across a training year in women collegiate lacrosse athletes. J Strength Cond Res 39(11): 1186–1193, 2025—Body composition and athlete load management are vital to adequate training stimuli and to mitigate neuromuscular (NM) fatigue. Research is limited regarding NM performance (NMP) in women lacrosse athletes. Therefore, the purpose of this study was to investigate changes in NMP in women lacrosse athletes across a training year. Collegiate women lacrosse athletes ( n = 9, mean ± SD ; age = 19.1 ± 0.9 years, height = 168.4 ± 6.8 cm, body mass = 68.0 ± 8.1 kg) completed countermovement jump (CMJ) and isokinetic strength (IS) testing of dominant and nondominant legs 4 times throughout the season: preseason start, preseason end, in-season end, and off-season end to assess NMP. Measures included (a) CMJ output variables of reactive strength index modified (RSImod), jump height, relative values of braking force, peak power, peak propulsive force, impulse; (b) CMJ strategy variables of time-to-takeoff, eccentric duration, concentric duration, relative braking time, CMJ depth; and (c) IS relative peak torques of quadriceps and hamstrings musculature. Secondary measures including body composition variables of body mass, % body fat (%BF), and fat-free mass. Repeated measures ANOVA with Bonferroni post hoc analysis assessed changes in CMJ and IS parameters to determine patterns in NMP ( p < 0.05). Changes observed from preseason start to offseason end included increased CMJ depth ( p = 0.019), relative braking time ( p = 0.009), and %BF ( p = 0.01). The IS variables increased throughout the training year, except for a decrease during preseason, perhaps indicative of overreaching. Negative changes in alternative CMJ variables and body composition reduced NMP, which highlights the importance of off-season program design and implementation to elicit desired training adaptations.