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.

Dynamic Leap and Balance Test: Ability to Discriminate Balance Deficits in Individuals With Chronic Ankle Instability.

CONTEXT: The Dynamic Leap Balance Test (DLBT) is a new dynamic balance task that requires serial changes in base of support with alternating limb support and recovery of dynamic stability, as compared with the Y modification of the Star Excursion Balance Test (Y-SEBT), which assesses dynamic stability over an unchanging base of support. OBJECTIVES: To assess the dynamic balance performance in 2 different types of dynamic balance tasks, the DLBT and the SEBT, in subjects with unilateral chronic ankle instability (CAI) when compared with matched controls. The authors hypothesized that the DLBT score would significantly differ between the CAI involved and uninvolved limbs (contralateral and healthy matched) and demonstrate a modest (r = .50) association with the SEBT scores. DESIGN: Case-control. SETTING: Controlled laboratory. PARTICIPANTS: A total of 36 physically active adults, 18 with history of unilateral CAI and 18 without history of ankle injury, were enrolled in the study. CAI subjects were identified using the Identification of Functional Ankle Instability questionnaire. INTERVENTIONS: The DLBT and the SEBT were performed in a randomized order on a randomly selected limb in CAI and healthy subjects. MAIN OUTCOME MEASURES: Time taken to complete the DLBT and the reach distances performed on the SEBT were compared between the CAI and the healthy subjects. RESULTS: There were no statistically significant differences (P < .05) in SEBT reach distances between groups. The DLBT time was greater (P < .01) for unstable ankles compared with the stable ankle. The authors found no correlation (P > .05) between DLBT time and any of the SEBT reach distances suggesting that the DLBT provides unique information in the assessment of patients with CAI. CONCLUSION: The DLBT challenges the ability to maintain postural control in CAI subjects differently than the SEBT. There is a need of more dynamic balance assessment tools that are functional and clinically relevant.

Responsiveness of the double limb lowering test and lower abdominal muscle progression to core stabilization exercise programs in healthy adults: a pilot study.

Low back pain (LBP) is one of the most prevalent and expensive health care problems in the United States. Studies suggest that stabilization exercise may be effective in the management of people with LBP. To accurately assess the effect of stabilization programs on muscle performance, clinicians need an objective measure that is both valid and reliable. The purpose of this study was to determine whether the double limb lowering test (DLLT) and lower abdominal muscle progression (LAMP) can detect a change in abdominal muscle performance after stabilization exercises. Eleven healthy participants (4 men and 7 women) were randomly assigned to either a specific stabilization exercise (SSE) or general stabilization exercise (GSE) group and were evaluated by the DLLT and LAMP before, during, and at the end of 8 weeks of training. Subjects attended exercise sessions twice per week over 8 weeks. No significant difference in pretest performance existed between the 2 groups. No significant difference was detected with the DLLT for either the SSE or GSE over time or when groups were combined. The LAMP detected a significant difference for the combined groups and GSE but not SSE over time. These data indicate that the LAMP is sensitive to change after a spinal stabilization program, whereas the DLLT does not detect a change after these programs. Furthermore, the GSE was more effective in producing these changes. Additional testing of these assessments is necessary to further validate these tests and to identify specific populations for which these tests may be most appropriate.

Standing flexion deficits predict self-reported outcomes in women after ipsilateral hamstring anterior cruciate ligament reconstruction.

PURPOSE: To profile the standing flexion angle and its association with subjective outcomes in ipsilateral hamstring tendon autograft anterior cruciate ligament-reconstructed patients. A secondary aim was to describe prone position-measured hamstring strength as a predictor of flexion angle. METHODS: Fifteen women (mean age, 20.47 ± 1.96 years; mean height, 1.69 ± 0.08 m; mean weight, 68.51 ± 12.64 kg; mean Tegner score, 6.80 ± 1.52), at a mean of 25.93 ± 11.25 months after surgery, were matched to 15 healthy participants by sex and approximate age, height, mass, and activity level (mean age, 20.93 ± 1.22 years; mean height, 1.65 ± 0.06 m; mean weight, 66.52 ± 10.69 kg; mean Tegner score, 6.13 ± 1.06). The independent variable was leg condition (involved, uninvolved, or matched). Dependent variables included goniometric flexion angle, Knee Injury and Osteoarthritis Outcome Score (KOOS) subscale scores, and absolute isokinetic hamstring strength. We used 1-tailed paired and 2-sample t tests to analyze side and group differences, respectively. Corresponding effect sizes (d) were also quantified. Linear regression assessed relations between flexion angle and the KOOS, as well as strength and flexion angle. P < .05 denoted statistical significance. RESULTS: The involved leg showed a significantly lesser flexion angle (112.9° ± 8.1°) compared with the uninvolved leg (116.1° ± 8.4°, P = .024) and matched leg (117.1° ± 4.5°, P = .044), with corresponding weak side (d = 0.380) and strong group (d = 0.958) effect sizes. Significant associations existed between flexion angle and subjective outcomes (r(2) = 60.3% and P = .001 for KOOS pain subscale, r(2) = 37.8% and P = .015 for KOOS subscale for function in activities of daily living, and r(2) = 39.2% and P = .012 for KOOS subscale for function in sports and recreation) for the involved leg. Hamstring strength was not a significant predictor of flexion angle for all legs (P > .05). CONCLUSIONS: Our results support the hypotheses that standing flexion angle insufficiencies exist for the involved leg, superior subjective outcomes are associated with greater flexion capacity, and hamstring strength at deep knee angles does not predict the standing flexion angle. LEVEL OF EVIDENCE: Level IV, therapeutic study, case series.

Electromyographic and kinetic analysis of two abdominal muscle performance tests.

BACKGROUND: In order to accurately assess the abdominal muscles, clinicians need valid clinical measures. The double leg lowering test (DLLT) and lower abdominal muscle progression (LAMP) are two common tests of abdominal muscle performance. The purposes of this study were to determine the relation between surface electromyographic (EMG) activity during the DLLT and LAMP levels; hip joint resultant moments and DLLT and LAMP levels; and the two measures of DLLT and LAMP. METHODS: Ten healthy participants were tested under both conditions. Surface EMG activity of the abdominal muscles was obtained, while pelvic movement was detected simultaneously. RESULTS: A moderate to strong association was found between rectus abdominus muscle activity and a moderate association with the external obliques with both test levels. For the internal oblique/transversus abdominus, a moderate and weak association was found with the DLLT and LAMP, respectively. A very strong association existed between the hip resultant joint moments (RJM) and the DLLT, while there was a weak correlation between hip RJM and the LAMP. No significant correlation was found between the DLLT and LAMP grades. CONCLUSIONS: This finding suggests that these tests may measure different qualities of muscle performance and provides preliminary support for their use. Further evaluation of these assessments with clinical populations is necessary.

Quality of systematic reviews on specific spinal stabilization exercise for chronic low back pain.

STUDY DESIGN: Systematic literature review. OBJECTIVE: To evaluate the quality of systematic reviews (SRs) on specific stabilization exercises for chronic low back pain (LBP). BACKGROUND: Multiple SRs regarding the effectiveness of lumbar stabilization exercises for people with chronic LBP have been published. As more SRs are published, the more it is recognized that, like other forms of research, methodological quality affects the validity of, and conclusions drawn from, the data. METHODS: A search of MEDLINE, CINAHL, and Embase was completed. Additionally, the PEDro database was screened and hand searching was completed. Included SRs had to contain randomized controlled trials examining a specific stabilization exercise program for the treatment of chronic LBP. Additionally, the assessed outcome measures had to include pain and/or disability measures. Literature reviews and clinical practice guidelines were excluded. Three reviewers independently assessed each SR for methodological quality. RESULTS: The search produced 665 SRs for review, of which 8 fulfilled the inclusion criteria. Consensus quality assessment scores ranged from 13/26 to 26/26, with an average of 20.7 points. Percent agreement and kappa values for individual criteria scores ranged from 50% to 92% and 0.25 to 0.85, respectively. Agreement was moderate to substantial across individual items, except for criterion 1. The intraclass correlation coefficient for overall score was 0.98 (95% confidence interval: 0.96, 0.99). CONCLUSION: This review of SRs identified several high-quality reviews that indicated some benefit of specific stabilization exercise programs for patients with nonspecific chronic LBP. LEVEL OF EVIDENCE: Therapy, level 1a.

Comparative immediate functional outcomes among cryotherapeutic interventions at the ankle.

PURPOSE/BACKGROUND: There is a lack of evidence detailing the immediate effects of different cryotherapy interventions at the ankle on functional outcomes such as balance and jumping tasks in a physically active population; therefore, the purpose of the present study is to compare the immediate effects of varied modes of cryotherapy applications to the ankle joint on Star Excursion Balance Test and vertical jump height performance. The authors hypothesized that cryotherapy would acutely decrease performance when compared to a control, and that concomitant compression would further hinder outcomes. METHODS: A crossover study was conducted in a controlled laboratory setting. Thirty (9 men, 21 women) participants (20.6 ± 1.0 years, 1.7 ± 0.1 m, 67.5 ± 11.7 kg) were enrolled. The independent variable was treatment mode; no ice, ice without compression and ice with compression. Dependent variables included center of pressure (COP) excursions, dynamic balance reach distances and vertical jump height for the dominant leg. Participants underwent three separate testing sessions separated by 72-hour rest intervals. The order of treatment and performance measures was randomized to prevent order effects. Normalized dynamic balance reach distances were assessed using the reliable modified Star Excursion Balance Test (SEBT). Center of pressure path length was assessed via a force platform during a single-legged static balance task under eyes-open and eyes-closed conditions. Relative vertical jump height was assessed using a single-legged vertical hop test. Group means and standard deviations were calculated by treatment mode. One-way analyses of variance with Tukey's post hoc test were used to calculate differences among treatment modes. p < 0.05 denoted statistical significance. RESULTS: No statistically significant differences existed for all the performance measures among treatment modes. CONCLUSIONS: These findings suggest no immediate differences in lower extremity performance outcome measures between the respective treatment modes applied to the ankle in a young, healthy and physically active population. Additional investigation is warranted to study the related delayed effects of these interventions. LEVELS OF EVIDENCE: III.

Can Chronic Ankle Instability Be Prevented? Rethinking Management of Lateral Ankle Sprains.

OBJECTIVE: To pose the question, "Can chronic ankle instability be prevented?" The evaluation and treatment of chronic ankle instability is a significant challenge in athletic health care. The condition affects large numbers of athletes and is associated with reinjury and impaired performance. The management of acute injuries varies widely but in athletic training has traditionally focused on initial symptom management and rapid return to activity. A review of practice strategies and philosophies suggests that a more detailed evaluation of all joints affected by the injury, correction of hypomobility, and protection of healing structures may lead to a more optimal long-term outcome. BACKGROUND: Sprains to the lateral ankle are common in athletes, and the reinjury rate is high. These injuries are often perceived as being isolated to the anterior talofibular and calcaneofibular ligaments. It is, however, becoming apparent that a lateral ankle sprain can injure other tissues and result in joint dysfunction throughout the ankle complex. DESCRIPTION: We begin by addressing the relationship between mechanical and functional instability. We then discuss normal ankle mechanics, sequelae to lateral ankle sprains, and abnormal ankle mechanics. Finally, tissue healing, joint dysfunction, and the management of acute lateral ankle sprain are reviewed, with an emphasis on restoring normal mechanics of the ankle-joint complex. A treatment model based on assessment of joint function, treatment of hypomobile segments, and protection of healing tissues at hypermobile segments is described.