Journal of Sports Medicine and Physical Fitness最新文献

Background: The aim of the study was to evaluate the construct validity of a novel constant-velocity Intermittent Recovery Test (IRT), designed to evaluate aerobic fitness in the field in soccer players.

Methods: Eighteen elite soccer players (age: 24.0±7.2 years, body mass: 82.9±6.8 kg, height: 184.7±5.2 cm) completed the IRT test, consisting of 50-m runs at 18 km/h (10-s/50 m), interspersed by a recovery time initially set at 17 s, gradually decreased up to 2 s, and then held constant until exhaustion. The maximum oxygen uptake (VO2max) measured by means of a portable gas analyzer, and the distance covered during the test were recorded, and their relationships with a selection of physical performance indicators collected during official matches were assessed with Pearson's r correlation coefficients.

Results: Small to moderate (r≤0.45), non-significant correlations (all P>0.05) were observed between VO2max and all the examined match performance variables. Conversely, the distance covered at exhaustion was largely and positively correlated (r=0.71 to 0.76) to total distance covered, average metabolic power, distance covered at high metabolic power, and acceleration/deceleration distance (all P<0.01).

Conclusions: The present findings reveal good construct validity of the distance covered in the IRT to predict match physical performance in elite soccer players.

Background: There is a need to better identify adverse responders to weight-loss interventions. The aim of this study was to: 1) identify potential predictive factors of adverse responders to weight loss; and 2) follow their long-term evolution.

Methods: One-hundred participants (56 females) with overweight (59.5±4.9 years) followed a 3-week intervention combining physical activity and diet followed by one-year monitoring, and were divided into three subgroups: 1) group A (N.=13) - "regainers" (weight regain during follow-up >100% of initial loss); 2) group B (N.=25) - "moderate regainers" (weight regain: 0-100%); and 3) group C (N.=46) - "weight relosers" (weight regain <0%). Body composition, food consumption, inflammatory and metabolic markers were assessed during the intervention and follow-up.

Results: Baseline energy intake was lower in group A(1518±361kcal/day) vs. group B (1929±451kcal/day) (P=0.013) and C(1882±572kcal/day) (P=0.024). Group A initially presented a healthier metabolic profile and the total score of compliance (diet + physical activity) was lower in group A during follow-up (group A:38.3% vs. B:49.2%(P=0.007) and C:72.1% (P<0.001). Ghrelin levels tend to decrease and peptide YY (PYY) to increase during follow-up in groups B and C while blunted responses were obtained in A.

Conclusions: Adverse responders might be characterized by a less unhealthy metabolic profile at baseline but also by less favorable changes in their satiety-regulating hormones during the one-year follow-up.

Background: Definitions of running-related injuries (RRI) in the literature are often determined by experts rather than by runners themselves. Incorporating the perspective of runners can provide valuable insights, particularly in the context of self-reported injury surveillance. This study aimed to develop a consensus definition of RRI by integrating the perspectives of recreational runners, acknowledging them as experts in their own injury experiences.

Methods: An e-Delphi method was employed to gather and refine the opinions of recreational runners. In the first two rounds, participants selected and rated terms relevant to the definition off RRI. The third and final round focused on achieving consensus by asking participants to rate their level of agreement with a definition developed by the authors based on their own responses in the previous two rounds. Consensus was defined as ≥75% agreement.

Results: Out of 163 respondents, 91 (55.8%) completed the first questionnaire and were included in the study. Of these, 67 (73.6%) completed the second questionnaire and 60 (65.9%) participated in the final validation round. A consensual definition was reached with 90% agreement: "Running-related pain, of musculotendinous and/or osteoarticular origin, localized to the lower limbs or pelvis and resulting in restriction (in speed, volume, time, distance) or cessation of running (training, competition) lasting at least 5 days or three sessions."

Conclusions: This consensual definition of RRI, developed from the perspectives of recreational runners, specifically addresses a gap in the literature regarding their experiential understanding of injury. It may be appropriate for self-report contexts in this population, offering a practical framework for future research and for surveillance of self-reported running-related injuries.

Background: Functional movement screen (FMS) is widely utilized in judo to assess movement patterns and identify potential deficiencies. The main objective of this study was to compare FMS results between high-performance (HP) and recreational-level (RL) judo athletes. Additionally, we examined asymmetries within each group.

Methods: A cross-sectional study was conducted on 49 male judo athletes, with 23 in the HP group and 26 in the RL group. Functional movement was assessed using the FMS battery, and differences between and within groups were analyzed.

Results: The HP group achieved a higher total FMS Score (17.09±1.38) compared to the RL group (16.50±2.42), but the difference was not statistically significant (P=0.51; r=-0.29). Significant differences were observed favoring HP athletes in the hurdle step test for the left leg (P=0.013; r=0.35) and in the rotator stability test, with HP athletes scoring higher on both the left (P=0.001; r=0.47) and right sides (P=0.030; r=0.31). In contrast, RL athletes demonstrated significantly better results in the right shoulder mobility test (P=0.028; r=0.31). Within-group analysis revealed asymmetries in HP athletes in the hurdle step test (right vs. left, P=0.042; r=0.41), whereas RL athletes showed asymmetries in the in-line lunge test (right vs. left, P=0.011; r=0.48).

Conclusions: The HP group demonstrated superior trunk rotational stability, suggesting that the rotator stability test may serve as a distinguishing factor among judo athletes of varying competitive levels. Additionally, shoulder mobility limitations in HP judo athletes were highlighted. The presence of movement asymmetries within both groups suggests potential imbalances that could impact injury risk and performance. These findings emphasize the importance of targeted training interventions to enhance movement quality and address asymmetries in judo athletes. Furthermore, judo appears to be an effective activity for improving functional movement even at the recreational level, as indicated by the relatively high FMS Scores among RL athletes.

Background: Muscle issues such as soreness, cramps, and strains are common consequences of sports exercise, making it critical to accurately identify the nature of muscle discomfort. It is important for not only medical professionals but also athletes and sports enthusiasts to independently identify and manage the risk of muscle strain.

Methods: This prospective observational study explores the effectiveness of measuring blood myoglobin (MB) levels as a method for detecting muscle strains among athletes. The study involved 30 male professional footballers monitored over one season. MB levels were measured the morning after players reported muscle pain. The analysis involved comparing these levels between two groups: one diagnosed with muscle strain through physical examination and magnetic resonance imaging (strain group), and the other with muscle soreness or cramps (non-strain group).

Results: The strain group, consisting of nine players, showed significantly higher MB levels (124±87.7 ng/mL) compared to the non-strain group, which included 15 players (49.9±29.6 ng/mL, P<0.01). A cutoff value of 60.3 ng/mL was determined via receiver operating characteristic analysis for suspected muscle strain cases. Subsequent logistic regression revealed that MB levels exceeding this threshold were associated with a 32.0-fold increase in the likelihood of muscle strain (P=0.005).

Conclusions: This finding suggests that blood myoglobin measurement can serve as a reliable tool for athletes to independently recognize the occurrence of muscle strains, even in settings without immediate medical oversight.

Introduction: This systematic review and meta-analysis aim to evaluate the efficacy and safety of exercise intervention in improving the rehabilitation outcomes of advanced lung cancer patients.

Evidence acquisition: According to PRISMA's statement, we searched the Web of Science, Medline, Embase, Cochrane Library, and ClinicalTrials.gov databases to collect randomized controlled trials on the efficacy and safety of exercise intervention in improving rehabilitation outcomes for lung cancer patients. These studies were established from the database until their publication in September 2024. A supplementary search was conducted on October 1, 2024. Perform statistical analysis using Review Manager 5.3.

Evidence synthesis: A total of 14 randomized controlled trials with 756 participants were included. The meta-analysis results showed that exercise intervention significantly improved quality of life (such as EORTC-QLQ-C30 scale MD=5.26, 95% CI: 2.41 to 8.11, P=0.0003; FACT-L scale MD-5.03, 95% CI: 0.51-9.55, P=0.03), fatigue (MD=-6.29, 95% CI: 9.94 to -2.65, P=0.0007), anxiety and depression (MD=-110, 95% CI: 1.67 to -0.54, P<0.0001; MD=1.96, 95% CI: 1.22 to 2.70, P<0.001), and exercise ability (MD=15.34, 95% CI: 4.07-26.61, P=0.008). However, exercise intervention did not improve dyspnea (MD=-0.86, 95% CI: -3.34~1.62, P=0.50 >0.05) in lung cancer patients.

Conclusions: Exercise intervention can significantly improve patients' quality of life, alleviate symptoms of fatigue, anxiety, and depression, enhance functional status and physical function. Therefore, it is recommended to include exercise intervention as part of the comprehensive treatment plan for cancer patients and further explore its best practices and potential mechanisms in future research.

Background: This study aims to determine the effects of high-intensity low-volume (HILV) versus low-intensity high-volume (LIHV) plyometric jump training on athletic performance in Taekwondo athletes.

Methods: Seventeen Taekwondo athletes (age: 19.35±1.31 yrs, height: 165.34±6.70 cm, weight: 60.17±8.31 kg, BMI: 21.92±1.81 kg·m^-2) were randomly assigned to either a HILV group (N.=8) or a LIHV group (N.=9). Participants completed plyometric jump training twice a week for 6 weeks, a total of 12 sessions. The training intensity and volume were set based on the Intensity Factor (IF) calculated from the ground reaction force, and the number of ground contacts, respectively. Athletic performance tests included countermovement jump (CMJ), drop jump (DJ), agility t-test, and 1RM leg press. The reactive strength index (RSI) was calculated from the height and the ground contact time of the DJ using a force plate.

Results: The results showed significant interaction effects for CMJ (P=0.038) and DJ (P=0.020). In the HILV group, both CMJ (P<0.001) and DJ (P=0.017) increased significantly. The LIHV group also demonstrated significant improvement in CMJ (P<0.001), while no significant changes were observed in DJ (P=0.072). For RSI (P=0.134), the t-test (P=0.443), and 1RM leg press (P=0.746), no interaction effects were observed, with only main effects over time being noted.

Conclusions: This study shows that six weeks of plyometric jump training improved jump ability, RSI, agility, and strength in Taekwondo athletes. HILV training was more effective than LIHV training in enhancing jump ability, highlighting the greater importance of intensity over volume in jump performance improvement.

Background: Markers of arterial stiffness including high Augmentation Index (AIx) are associated with cardiovascular events and all-cause mortality and are reduced with exercise training. In trained individuals, the AIx response to peak exercise (exercise delta AIx75 [Ex-AIx75]) may better help identify the effect of age and sex on arterial stiffening compared with conventional resting measures. This study aimed to determine the effect, and contribution of age, sex, peak oxygen (O2) uptake (V̇O2peak), mean weekly training load and lifetime training on resting AIx75, and Ex-AIx75 of healthy aerobic trained adults.

Methods: One hundred healthy aerobic trained adults (49 women, 51 men, being 48 younger [18-30 years], 52 older [40-60 years]) underwent non-invasive measurements of AIx75 at rest and post peak cycling exercise.

Results: Resting AIx75, and Ex-AIx75 were significantly higher (P<0.001) in the older group compared to the younger group. Peak O2 uptake made the largest unique contribution to resting AIx75 (P<0.001), followed by age, height, and sex. None of the variables made a significant unique contribution to Ex-AIx75.

Conclusions: In healthy aerobic trained adults, while age and sex are unique contributors of resting AIx75, V̇O2peak makes the largest unique contribution. Therefore, increasing V̇O2peak should be a primary component to consider for individuals who want to reduce their risk of CV events.

Background: The Apple Watch measures heart rate, but its validity decreases with high exercise intensities, so this study investigated whether pairing the Apple Watch with a polar chest strap could be more accurate than the Apple Watch alone in measuring heart rate during high intensity exercises and in recovery from exercises.

Methods: A cross-sectional study measured heart rate on the Apple Watch compared to the Apple Watch paired with the Polar chest strap on 30 healthy subjects. Each participant has done three minutes of low, moderate, and high exercise intensities using both the treadmill and cycle for 9 minutes each, followed by 3 minutes of recovery after each treadmill and cycle.

Results: There were excellent correlations between the Apple Watch and Polar chest strap during low (r=0.99 Treadmill, r=0.99 cycle), moderate (r=0.99 treadmill, r=0.99 cycle), and high (r=0.96 treadmill, r=0.99 cycle), exercise intensities and in recovery from Treadmill and Cycle (r=0.97 treadmill, r=0.98 cycle). There were excellent correlations between the combined Apple Watch with Polar chest strap and the Apple Watch alone during low (r=1.00 treadmill, r=0.99 cycle), moderate (r=0.99 treadmill, r=0.99 cycle), and high (r=0.99 treadmill, r=0.99 cycle) exercise intensities and in recovery from Treadmill and Cycle (r=1.00 treadmill, r=0.99 cycle).

Conclusions: The Apple Watch is valid for measuring heart rate during low to moderate exercise intensity, and its validity can be increased at high exercise intensities or after recovery from exercise by adding it to the Polar chest strap and holding hands on the handrail while performing exercises.

Background: Although lactate threshold (LT) tests are widely used by athletes to evaluate endurance performance, such tests are not commonly applied in health controls among recreationally active subjects. This study aimed to investigate the test-retest reliability of walking as an exercise modality during LT testing and compare the test outcomes with those obtained during running.

Methods: Twenty-three male and female participants (25±3 year, 172±8 cm, 70±13 kg, and maximal oxygen consumption [VO2max] 51±5 mL·kg^-1·min^-1) performed four LT tests within 2-3 weeks, either using walking or running (two tests in each condition) protocols. The running tests were performed on a flat treadmill, and the pace increased by 1 km·h^-1 for each stage. During the walking tests, the pace was set to 6.5 km·h^-1, and the incline increased by 2.5% for each stage. LT was determined based on a fixed blood lactate concentration of 4.0 mmol·L^-1.

Results: Similar reliability values were observed for the walking and running protocol, and all between-trial differences were trivial or small. Significantly lower heart rate at LT was observed for the walking vs. running condition, but all between-modality differences were trivial or small. Analysis revealed that LT occurred at a slightly lower workload in walking than running (11.4±1.4 vs. 12.0±1.3 metabolic equivalents [METs]).

Conclusions: Given the trivial to small differences in LT variables observed between running and walking, these two protocols cannot be used interchangeably. However, the present study shows that walking represents an alternative exercise modality during LT testing in recreationally active subjects.