Yoga vs. Static Stretching: Recovery Impact on Male Athletes’ Post-HIIT Heart Rate, Respiratory Rate, Blood Pressure, and Heart Rate Variability Analysis

International Journal of Exercise Science 18(6): 79-91, 2025. Heart rate and heart rate variability indicate an athlete\u27s cardiovascular recovery and autonomic balance after intense exercise. While stretching aids recovery, its effects on autonomic balance are inconsistent. Yoga’s combination of postures, breathing, and relaxation may further activate the parasympathetic system, making it a promising tool for sports recovery. This study employed a crossover design to examine the effects of yoga and stretching on post 30-min session of high-intensity interval training (HIIT) recovery in male athletes. Twenty athletes of Mae Fah Luang University (Age 20.95±0.99 years old, VO2max 42.53±4.79 ml/kg/min) were given recovery methods, 15-min stretching and 15-min yoga following HIIT. Heart rate, blood pressure, respiratory rate, and heart rate variability were evaluated immediately after HIIT, 5-min, 10-min, 15-min of the recovery period, and at 24-hour after recovery. A Two-way repeated-measures analysis of variance (ANOVA) was employed to examine the interaction effects between different methods and time of recovery. A significance level of 0.05 indicated a statistically significant difference. The findings indicated a statistically significant interaction between the group and time of heart rate variability and respiratory rate (p\u3c0.05, effect size [ES] medium). Post-hoc analysis indicated that performing yoga showed a significantly lower respiratory rate at 5-min, 10-min, and 15-min compared to stretching (p\u3c0.05, ES large). Yoga demonstrated a noteworthy enhancement in heart rate variability during the 5-min and 10-min recovery periods in comparison to stretching. In summary, this study provides empirical evidence supporting the efficacy of yoga as a post-exercise recovery strategy following high-intensity interval training. The role of breathing, rhythmic muscle contractions, and deep relaxation in yoga appears to facilitate the recovery phase more effectively than stretching alone. This suggests incorporating yoga as an active recovery regimen

A Flexible Training Approach to Improving Concurrent Training Outcomes in Remote Trainees

International Journal of Exercise Science 18(8): 43-55, 2025. This study aimed to evaluate the effectiveness of a flexible, trainee-driven training program in improving concurrent training outcomes for individuals training remotely. The study employed a repeated-measures, parallel group design with 18 participants randomized into either a control group with fixed workouts or an experimental group with flexible workout selection based on perceived readiness. Participants were recreationally trained at baseline. Over a 16-week period, both groups completed assessments of strength and endurance, including deadlift, push-ups, and a two-mile run. The results indicated no significant difference in overall fitness improvements between the two groups, with both showing meaningful progress in strength and endurance measures. However, adherence rates were notably lower in the flexible group as the study progressed, potentially due to decision fatigue. Statistical significance was set at ρ ≤ 0.05, with main effects of time showing significant improvement in fitness scores across all groups. The findings suggest that while flexible programming offers similar benefits to traditional fixed programs, it may require strategies to maintain adherence over longer periods. Practical applications include the potential for flexible training to be used effectively in remote settings, particularly for populations like military personnel with varying access to fitness resources

An Exploratory Study Comparing the Metabolic Responses between the 12-3-30 Treadmill Workout and Self-Paced Treadmill Running

International Journal of Exercise Science 18(6): 56-64, 2025. The fitness movement in the United States has evolved substantially since its emergence in the late 20th century, with social media platforms like YouTube and TikTok now playing a pivotal role in disseminating fitness programs and associated claims. One program that has gained considerable popularity is the 12-3-30 treadmill workout (12-3-30), which involves walking at a 12% grade at 3 mph for 30 minutes. Despite widespread claims about its effectiveness in burning fat and calories, there is a lack of peer-reviewed scientific studies evaluating these claims. The present study investigated metabolic responses to 12-3-30 compared to self-paced treadmill running, with both sessions matched for total energy expenditure. Sixteen participants (7 female, 9 male) completed both sessions in a controlled laboratory setting, where metabolic data were collected using a metabolic analyzer. The measures recorded were completion time, total energy expenditure, energy expenditure rate, and substrate utilization (percentage of carbohydrate [%CHO] and fat [%FAT]). The results showed that, when matched for total energy expenditure, 12‑3‑30 had a significantly longer completion time, lower energy expenditure rate, higher %FAT, and lower %CHO than self-paced running. While 12-3-30 may be less time efficient than self-paced running for expending energy, it may be more advantageous for individuals aiming to increase fat utilization. The present study enhances our understanding of the metabolic demands associated with a trending fitness program and highlights the importance of scientifically evaluating such programs to provide evidence-based recommendations

The Effects of Augmented Feedback, Focus of Attention, and Monetary Reward on Vertical Jump Height: A Replication Study

International Journal of Exercise Science 18(7): 13-26, 2025. Reproducibility and replicability of published empirical scientific evidence are fundamental for verifying key findings, identifying errors and/or boundary conditions, and upholding rigorous research standards. For this replication study, the primary goal was to assess the replicability of the findings from Wälchli et al. (2016), which investigated the role of augmented feedback (AF), external focus of attention (EF), and reward (RE), as well as a combination of these conditions on countermovement jump height. The original study sample included 18 resistance-trained male and female participants, while this replication included 38 (19 male, 19 female). Participants performed maximal countermovement jumps in six different conditions: neutral (NE), aF, RE, aF + EF, aF + RE, and aF + EF + RE. Results showed a non-significant effect of condition on jump height (p = 0.612, ηp2= 0.015) which was in contrast to the original study. Furthermore, the replication effect size was not compatible with the original effect size estimate as it was significantly smaller. There was also no significant effect of condition on muscle excitation or kinetic variables. The present study demonstrated that each combination of AF, EF, and RE did not affect vertical jump performance. Therefore, we were unable to replicate the findings from the original study in this close replication

The Relationship Between Lower-Body Flexibility and Running Performance in a Half Marathon Downhill Running Event

International Journal of Exercise Science 18(3): 1-12, 2025. Although previous studies examining treadmill or relatively flat overground running events have found relationships for running performance and flexibility, no study has examined these outcomes during downhill events, including between sexes. Therefore, the purpose of this study was to determine if a relationship exists between lower body flexibility and running performance in recreational adult male and female distance runners competing in a downhill half marathon race. Recreational (n=11 male, n=19 female) adult distance runners completed this study. On the day prior to the race, participants performed a standardized warm-up, followed by determining their sit-and-reach flexibility. The next day, individuals ran their race and their performance scores were recorded using the race organizers website. Pearson correlation coefficients (r) were determined between race time and flexibility. Sex differences were determined using independent t-tests, with significance set at p\u3c0.05. A significant relationship was observed across all participants for race performance and flexibility (r=0.42, p=0.01), but was not when separating out male (r=0.53, p=0.10) and female (r=0.32, p=0.19). Sex differences were observed for performance times (male: 6692.0±920.1 vs female: 7613.3±1073.5 sec., p=0.021, d=0.84), but not flexibility (male: 28.1±8.4 vs female: 32.9±10.8 cm, p=0.19, d=0.47). Flexibility is an important component of running performance, but may have less predictive ability by sex in downhill running performance in recreational runners

Comparison of Cardiorespiratory Fitness Testing Measures in Children

International Journal of Exercise Science 18(8): 65-78, 2025. There is currently an exponential increase in the prevalence of childhood obesity thus warranting the demand to appropriately measure and evaluate cardiorespiratory fitness within educational settings. The aims of this study were to (1) compare measured peak oxygen consumption (VO2peak), heart rate peak (HRpeak), and 1-min heart rate recovery (HRRec) responses obtained using a GXTmax and the PACER test; and (2) compare the VO2peak from the GXTmax and PACER test to a PACER prediction equation (ScottEqua). Methods: This study included 32 (16 boys) children. Despite not having maturational assessments on these children, we limited the subject’s age range from 10-11 year old’s to decrease the possibility of including additional variability in pubertal status. The participants were classified by body mass index for age and sex percentiles (BMI%) as Healthy-Weight (HW BMI% ≤ 85th percentile) or At-Risk (AR BMI% \u3e 85th percentile). Participants completed the GXTmax and PACER tests while wearing a portable metabolic system to measure VO2peak; and these measures were compared to the estimated VO2peak using the ScottEqua. Group mean differences and correlation analysis were used to compare the testing and predictive procedures. Results: We found no significant differences between the GXTmax and PACER VO2peak; however, the Scott Equa VO2peak was significantly greater than these measures. HRpeak was significantly greater during the GXTmax; but no significant HRRec were found. Conclusions: The PACER and GXTmax provide similar VO2peak measures; however, PACER prediction equations should be used with caution in children 10-11 years

The Psychometric Performance of State Mindfulness Scales Around Sitting and Walking on Desert Trails: A Pilot Study

International Journal of Exercise Science 18(4): 27-42, 2025. State mindfulness is a dynamic construct reflecting current mindfulness, or purposeful attention to the present moment with openness, non-judgment, non-reactivity, and acceptance. Despite its popularity and research in psychology and medicine, measuring state mindfulness remains a challenge. Validity and reliability of the State Mindfulness Scale (SMS) and State Mindfulness Scale for Physical Activity (SMS-PA) in applied settings like nature require more data to be established. This pilot study aimed to evaluate these scales and introduce a new, one-item scale, the Visual Analog Scale-Mindfulness (VAS-M), for quicker mindfulness assessment. Participants completed the SMS, SMS-PA, and VAS-M upon arrival at a desert trail, after 10 minutes of sitting, and after 10 minutes of walking. A subset repeated the intervention 24 hours later. The study found that the SMS and SMS-PA could be given before, during, and after nature immersion. The SMS-PA showed evidence of concurrent validity with the SMS (ρ = .89, p \u3c .001). However, the VAS-M did not meet the criteria for concurrent validity with the other scales. None of the scales met the criteria for test-retest reliability. This study underscores the need to validate state mindfulness scales, especially in non-laboratory settings. While the SMS-PA shows promise, further validation and refinement of the VAS-M are needed. The findings enhance our understanding of measuring state mindfulness, particularly in natural environments. While the scales are already in use, our study helps address gaps in evidence and informs future decisions about their application

EPIDEMIOLOGICAL COMPARISON OF INJURIES BETWEEN A NAIA MEN’S AND WOMEN’S SOCCER PROGRAM

BACKGROUND: Previous research comparing injury rate differences among NCAA Injury Surveillance Program (ISP) and one NAIA women’s soccer program (Truett McConnell University (TMU)) found remarkable injury risk among the NAIA soccer players. Greater attention has been placed on injury prevention and strength and conditioning as a result. The purpose of this study was to examine the sex differences between male and female soccer players at TMU for the 2021-2022 and 2022-2023 seasons. The findings can bring more awareness to injuries among soccer players and the need for injury prevention programs. METHODS: An epidemiological study was conducted to investigate injury rates between men and women’s soccer at TMU, to investigate the difference of injury rates between women’s soccer seasons 2021-2022 and 2022-2023; and, to investigate the difference of injury rates between men’s soccer seasons 2021-2022 and 2022-2023. Injury data was collected by a staff certified athletic trainer (AT) from TMU using CSMI SportsWare Online. The study identified incident rate ratios (IRR) by finding the total number of knee injuries divided by the total number of athlete-exposures (AEs). The study compared the IRR of men’s and women’s soccer, compared the IRR of women’s soccer during the 2021-2022 and 2022-2023 seasons; and, compared the IRR of men’s soccer during the 2021-2022 and 2022-2023 seasons. RESULTS: The rate of injury in women’s soccer was higher in both regular seasons. Women’s soccer IRR (1.625/1,000 AE) compared to the men’s soccer at TMU (0.615/1,000 AEs) for the 2021-2022. The rate of injury in women’s soccer was higher (1.357/1,000 AEs) compared to the rate of injury in men’s soccer (0.073/1,000 AEs) for the 2022-2023 season. The rate of injury in women’s soccer at TMU for the 2021-2022 season was higher (1.188/ 1,000 AEs) compared to the rate of injury of women’s soccer for the 2022-2023 season (0.842/1,000 AEs). The rate of injury in men’s soccer at TMU for the 2021-2022 season was higher (1.75/1,000 AEs) compared to the injury rate of men’s soccer for the 2022-2023 season (0.571/1,000 AEs).CONCLUSIONS: During the 2022-23 academic year a certified strength and conditioning specialist was hired at TMU and the IRR for both teams dropped. The rate of injury of women’s soccer was however almost twice as high as the injury rate of men’s soccer at TMU for the seasons 2021-2022 and 2022-2023. The rate of injury among men and women’s soccer during the season 2021-2022 was almost twice as high as the injury rate among men and women’s soccer during the season 2022-2023. The results of this study highlights the need for injury prevention programs among both men and women’s soccer players at TMU and soccer in general due to the physical nature of the sport

DIFFERENCE IN TREATMENT PRACTICES OF EMERGENCY MEDICINE VS. FAMILY MEDICINE TRAINED SPORTS MEDICINE PHYSICIANS

BACKGROUND: Previous studies have investigated treatment practices between orthopedic surgeons and primary care sports medicine physicians; however, our study solely looks at primary care physicians and investigates if the primary specialty training impacts treatment. The aim of this study is to evaluate differences in treatment of acute injuries based on primary specialty. METHODS: Patients that fit inclusion criteria at Steadman Hawkins orthopedic outpatient clinics were included. Treatment recommendations were compared between Emergency Medicine (EM) and Family Medicine (FM) trained Sports Medicine Physicians. Treatment options evaluated were: additional imaging, medications, injections, physical therapies, durable medical equipment (DME, e.g. splint, brace), activity restrictions, and surgery or follow up. Data was input into REDCap and analyzed using Fisher’s exact test. RESULTS: 35 patients were included, 12 received care from EM physicians and 23 from FM physicians. FM physicians prescribed medication more frequently than EM physicians (52.2% vs 0%, p=0.002). There were no significant differences between frequency of recommendations for additional imaging, injection, physical therapy, stabilization, activity restrictions, surgery or follow up. There was a non-significant trend with EM physicians prescribing more DME than FM physicians (83.3% vs 56.5% of patients, p=0.11). CONCLUSIONS: The data collected suggests there are differences in documented treatment recommendations based on the residency completed prior to sports medicine fellowship. More specifically, there was a statistically significant difference in FM physicians prescribing medication more frequently than EM physicians

ASSOCIATION BETWEEN RESTING HEART RATE VARIABILITY AND NOCTURNAL BLOOD PRESSURE IN YOUNG ADULTS

BACKGROUND: Healthy circadian variation in arterial blood pressure (BP) is characterized by nocturnal dipping. Elevated BP or attenuated BP dipping during sleep is associated with greater risk for cardiovascular diseases. Moreover, cardiac-autonomic activity is associated with BP dipping patterns in clinical populations, but whether this relationship exists in apparently healthy adults is unclear. Therefore, the purpose of this study was to quantify associations between cardiac-autonomic activity, indexed via resting heart rate variability (HRV), and nocturnal BP characteristics in young adults. METHODS: Twenty-nine apparently healthy young adults (n = 13 males, 23 ± 4 yrs, 23 ± 3 kg/m2, n = 16 females, 20 ± 2 yrs, 23 ± 3 kg/m2) were included in the analysis. Resting HRV was obtained in the laboratory following an overnight fast. Five-minute electrocardiographic recordings were obtained in the supine position following a five-minute stabilization period. Short-term HRV parameters of interest included the mean RR interval, standard deviation of normal RR intervals (SDNN), and root-mean square of successive differences (RMSSD). Participants left the laboratory wearing an ambulatory BP monitor on their upper arm programmed to perform recordings every 20 minutes during awake hours and every 30 minutes during sleeping hours. Self-reported bedtime and wake time were used to identify awake and asleep periods. Absolute BP dipping was quantified as awake BP minus asleep BP. RESULTS: In males, asleep diastolic BP (54.7 ± 4.1 mmHg) was associated with SDNN (58.7 ± 17.9 ms, r = -0.57, P \u3c0.05) and RMSSD (60.5 ± 25.9 ms, r = -0.56, P \u3c0.05). Additionally, systolic BP (12.1 ± 6.6 mmHg, r = 0.64) and diastolic BP dipping (22.8 ± 7.4 mmHg, r = 0.59) were associated with SDNN (Ps \u3c0.05). No associations between any HRV and BP values were observed for females (Ps \u3e0.05). CONCLUSIONS: Our findings reveal sex differences in the association between resting short-term cardiac-autonomic activity and nocturnal BP characteristics in healthy young adults. HRV is an accessible and modifiable (e.g., via aerobic exercise) biomarker that may be a useful target for young adult males to improve circadian variation in BP and reduce cardiovascular disease risk. FUNDING: Supported by Georgia Southern University Faculty Research Committee Research Seed Funding Award