ECSS Paris 2023: CP-MH04
INTRODUCTION: Return to play (RTP) metrics post ACL-R are measured through six different external parameters. Four of these parameters compare the ACL-R limb to the contralateral limb, attempting to approach symmetry in the limbs. While external symmetry aids in the ability to understand where in the recovery process the athlete is, an internal parameter could increase the accuracy of the assessment by providing insights into the underlying biomechanical and physiological factors influencing the athletes performance. Muscle oxygen saturation (SmO2) has emerged as a biomarker of interest to quantify changes in muscle function during workouts. We hypothesize that differences in SmO2 could be attributed to less efficient O2 use in the ACL-R limb compared to the contralateral limb. The ultimate objective is to mitigate reinjury risks by tailoring rehabilitation strategies based on a comprehensive understanding of the athletes physiological responses and promoting symmetrical recovery patterns. This study seeks to utilize SmO2 as an objective internal variable to guide return to sport following ACL-R. METHODS: In this study, approved by the Lehigh University Institutional Review Board at Lehigh University, we utilized near-infrared spectroscopy (NIRS) to assess SmO2 differences in the vastus medialis muscle. Additionally, we utilized a heart rate monitor to assess alterations in cardiac function among four Division 1 football athletes, aged 18-22, at various stages after ACL-R surgery. Measurements were taken during distinct rehabilitation time points. The athletes performed two sets of 20 repetitions of quad sets and single-leg raises. RESULTS: Our ongoing study has yielded promising initial evidence regarding SmO2 convergence between the collateral and surgical legs during rehabilitation exercises for athletes within 4 months post ACL-R surgery. The data collected showed an average SmO2 of 70% for surgical and 50% for contralateral within one month of surgery. At around 4 months, on average, SmO2 for surgical was 58% and contralateral was 62%. Notably, we observed a convergence in SmO2% after this relatively short period, which deviates from the expected 6-month timeline. To further validate these findings, our future work will focus on expanding the sample size to ensure robustness and generalizability. By doing so, we aim to provide valuable insights that can inform rehabilitation strategies and enhance return-to-play protocols for Division 1 football athletes recovering from ACL-R surgery. CONCLUSION: Our investigation into SmO2 variations in the vastus medialis following ACL-R surgery has found asymmetries between the surgical and contralateral legs. This highlights the critical importance of continuous monitoring of SmO2 during rehabilitation to tailor recovery strategies effectively. The findings not only contribute valuable insights for optimizing physiological responses and refining return-to-play protocols in athletes but also to other areas in medicine where atrophy occurs.
Read CV Dhruv SeshadriECSS Paris 2023: CP-MH04
INTRODUCTION: Long distance running is a popular recreational activity, and participation in marathon and half marathon races has increased over the past several decades. Running-related injuries (RRI) are common and have a multifactorial etiology based on location and type of injury. Asymmetries in lower extremity lean mass may contribute to unbalanced muscle strength and functional loading between limbs. The impact of asymmetries in lower extremity lean mass (LELM) on RRI incidence remains unclear, particularly in recreational endurance runners. The purpose of this study was to prospectively evaluate the impact of LELM asymmetry on incidence of RRIs in a cohort of runners training for a half or full marathon. METHODS: 153 (77M/76F; Age: 35.8+/-11.7yrs) recreational runners performed a maximal graded treadmill exercise test 10-12 weeks before their event (baseline), and a second test 3-4 weeks pre-race (83.8+/-29.7 days apart). Total body Dual Energy X-ray Absorptiometry scans were performed at each visit to evaluate total LELM and LELM asymmetry. Participants were instructed to maintain their typical training habits over the course of the study and were classified as injured or healthy based on self-reported injury status between visits. Injuries were defined as any running-related musculoskeletal impairment causing a self-reported disruption in training. Independent t-tests were used to evaluate differences in LELM asymmetry and VO2max between healthy and injured groups. RESULTS: Baseline VO2max (M=51.6+/-7.6ml/kg/min, F=46.2+/-6.7ml/min/kg; p<.001), and total LELM (M=76.7+/-4.7%, F=67.0+/-5.9%; p<.001) were significantly different between genders, but LELM asymmetry did not differ by gender (p>.05). 18 participants (11.7%) sustained an injury between visits. No significant differences in LELM asymmetry were present between healthy and injured participants or when divided by gender (p>.05). Injuries were subdivided by type (muscle, tendon, bone, ligament, or unknown; n=6 ,4, 3, 2, 3 respectively), and by location (hip/pelvis, knee/thigh, shank, foot/ankle; n=4, 8, 2, 4 respectively). Despite some difference in LELM asymmetry across injury types (ligament injury asymmetry of 4.86+/-0.57% vs. muscle asymmetry of 2.86+/-1.49%) and site (shank injury asymmetry of 4.39+/-0.28% vs. healthy participants 3.36+/-2.35%), low injury incidence precluded a meaningful assessment of those numbers. CONCLUSION: LELM asymmetry was not associated with RRI in our sample of recreational endurance runners training for a half or full marathon. The magnitude of asymmetry related to incidence of RRI may be greater than what was observed in the present sample. Alternatively, asymmetries in muscle functional capacity, independent of lean mass, may play a larger role on incidence of RRI in recreational runners. This study received funding from Apple Inc. The funding source had no role in the analysis and interpretation of the data or in the submission of this abstract.
Read CV Adam AudetECSS Paris 2023: CP-MH04
INTRODUCTION: Low back pain (LBP) is recognized as a significant health issue worldwide, particularly among athletes. A history of LBP is considered the most consistent risk factor, possibly attributed to changes in motor control. The previous study has identified altered lumbopelvic control in athletes with a history of LBP through movement testing. However, the abilities of lumbopelvic control in collegiate athletes remain unknown, and there is no existing research exploring the outcome differences in high and low-threshold tests. The study aims to examine lumbopelvic control in collegiate athletes and assess potential differences between those with and without LBP experiences through a series of motor control tests. METHODS: This was a case-control study performing a series of motor control tests on twenty participants with and without a history of LBP. The assessments encompass single-joint tests and multi-joint control tests in high and low thresholds. Each test is taught and practiced 3-8 times, with recordings from frontal and lateral views utilizing cameras for subsequent analysis of the tests. Blinded to participants LBP history, a physiotherapist scored the subject’s performance on each test. The significance differences between the groups were calculated with the Mann-Whitney U test and the p-value was set at 0.05. RESULTS: Subjects with a history of LBP exhibited poorer lumbopelvic control compared to the control group. The significant differences between groups with and without a history of LBP were particularly marked for the bent knee fall out (p=0.017), double knee swing (p=0.036), single leg 1/4 squat + hip turn (p=0.005), short Lunge + front knee swing, lean & rear leg lift (p=0.004), pelvic bridge + arms overhead + heel Lift + 1 leg extension & lower (p=0.036), and lateral stair hop + rotational landing control (p=0.047). The remaining tests, including single-joint and multi-joint high-threshold tests, didn’t show significant differences between groups. CONCLUSION: This study indicates that the multi-joint low-threshold lumbopelvic control tests are more effective in discriminating between collegiate athletes with and without a history of LBP. Our results provide an aspect of screening on the potential risk of LBP. In the future, clinical practitioners can refer to research findings to tailor training programs targeting weaknesses in collegiate athletes, and even predict the occurrence of LBP to achieve prevention goals.
Read CV Chih-Yuan WangECSS Paris 2023: CP-MH04