Browse

Context: Exercise-induced muscle damage (EIMD) is prevalent especially in sports and rehabilitation. It causes loss in skeletal muscle function and soreness. As there are no firm preventive strategies, we aimed to evaluate the preventive efficacy of nonthermal 448-kHz capacitive resistive monopolar radiofrequency (CRMRF) therapy after eccentric bouts of EIMD response in knee flexors. Design: Twenty-nine healthy males (age: 25.2 [4.6] y) were randomized in control group (CG; n = 15) and experimental group (EG; n = 14) where EG followed 5 daily 448-kHz CRMRF therapies. All assessments were performed at baseline and post EIMD (EIMD + 1, EIMD + 2, EIMD + 5, and EIMD + 9 d). We measured tensiomyography of biceps femoris and semitendinosus to calculate contraction time, the maximal displacement and the radial velocity of contraction, unilateral isometric knee flexors maximal voluntary contraction torque, and rate of torque development in first 100 milliseconds. Results: Maximal voluntary contraction torque and rate of torque development in first 100 milliseconds decreased more in CG than in EG and recovered only in EG. Biceps femoris contraction time increased only in CG (without recovery), whereas in semitendinosus contraction time increased in EG (only at EIMD + 1) and in CG (without recovery). In both muscles, tensiomyographic maximal displacement decreased in EG (in EIMD + 1 and EIMD + 2) and in CG (without recovery). Furthermore, in both muscles, radial velocity of contraction decreased in EG (from EIMD + 1 until EIMD + 5) and in CG (without recovery). Conclusion: The study shows beneficial effect of CRMRF therapy after inducing EIMD in skeletal muscle strength and contractile parameters in knee flexors.

Context: Meniscal injury is a common pathology, and the postoperative rehabilitation program is essential to patients after surgery. However, the optimal rehabilitation plan after meniscus suture is still controversial. Objective: To compare the clinical outcomes between accelerated rehabilitation and restricted programs in patients with meniscus suture (with or without anterior cruciate ligament reconstruction, ACLR). Evidence Acquisition: Four databases, including PubMed, Ovid, Embase, and the Cochrane Library, were searched up to November 2021. This study only included studies comparing the clinical outcomes between accelerated (immediate range of motion and weight-bearing) and restricted rehabilitation (immobilization and progressive weight-bearing) for meniscus suture. All selected studies were divided into 2 subgroups: isolated meniscus suture or combined with ACLR. The Lysholm score, Tegner score, and Knee Injury and Osteoarthritis Outcome Score were evaluated in simple meniscus sutures no less than 1 year. Failure rate was evaluated in both groups, and the tunnel enlargement was additionally evaluated in patients who underwent ACLR. Evidence Synthesis: Eleven studies with 612 patients were eligible for analysis. The accelerated group included 4 studies with 330 participants, while the restricted group included 7 studies with 282 participants. For the patients after isolated meniscus suture, the accelerated group achieved higher Lysholm scores (mean difference = −4.66; 95% confidence interval, −8.6 to −0.73; P = .02; I ² = 88%) than the restricted group. For the patients after meniscus suture with ACLR, patients undergoing accelerated rehabilitation were associated with a significantly larger tibial tunnel enlargement in the anterior–posterior view (mean difference = −7.08; 95% confidence interval, −10.92 to −3.24; P = .0003; I ² = 0%) and lateral view (mean difference = −10.33; 95% confidence interval, −16.9 to −3.75; P = .002; I ² = 17%). Conclusion: This meta-analysis evaluated the effects of postoperative rehabilitation in either accelerated or restricted programs in patients with meniscus lesions after repair. A significant higher mean self-reported function was discovered at final follow-ups in the accelerated group. However, a significant increase in tibial tunnel enlargement was also found in accelerated group.

Context: Whole-body vibration (WBV) training improves muscle strength and balance. Few studies have focused on the effects of WBV frequencies below 30 Hz. We aimed to investigate the effect of low-frequency WBV training on muscle activity, fatigue recovery, and oxygen consumption (VO₂). Design: Prospective single-group, repeated-measures study. Methods: In this controlled laboratory setting study, 20 healthy adults (age 23.26 [1.66] y) performed half squats at 0, 4, 6, 8, 12, 16, 20, 24, and 30-Hz WBV. Muscle activity was evaluated using the root mean square and peak electromyography amplitude of 6 muscles (iliocostalis, rectus abdominis, rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius) obtained via surface electromyography. VO₂ was measured during the squats using a gas analyzer, and fatigue recovery was evaluated using measurements of lactate after the squats and after a recovery period. Statistical significance was set at P < .05, and analysis of variance was conducted to determine differences in muscle activity, fatigue, recovery, and VO₂, with post hoc analyses as appropriate. Results: Of the 6 muscles measured, the muscle activity of the gastrocnemius alone significantly increased from 0 Hz at 4, 8, 12, 16, 24, and 30 Hz based on the root mean square values and at 4, 8, 12, and 30 Hz based on the peak electromyography amplitude values. There were no significant differences in the other muscles. There were no significant differences in VO₂ or in lactate levels. Conclusions: Low-frequency WBV during squat exercises significantly increased the activity of the gastrocnemius medialis only at specific frequencies in healthy young adults. Low-frequency WBV is safe and has the potential to increase muscle activity.

Clinical Scenario: Youth athletes may specialize in a sport of their choosing, or based on external pressures, to pursue elite status in that sport. Current evidence shows an association between highly specialized athletes and an increase in injuries as well as a connection between injury and lower health-related quality of life (HRQOL). Clinical Question: In college athletes, do early sport specialization characteristics (ie, age at specialization and degree of specialization) impact current HRQOL? Summary of Key Findings: The literature was searched for studies that investigated the age of specialization (early vs late) or degree of specialization (high, moderate, and low) and the impact on HRQOL. (1) The search returned 6 possible studies related to the clinical question. Three of the studies met the inclusion criteria and were used for this appraisal. (2) Two of the 3 included studies reported that highly specialized athletes noted lower HRQOL. (3) One study found there to be no significant difference in HRQOL between athletes who specialized early versus late but did find those who specialized early to have a greater incidence of injuries that required surgery. Clinical Bottom Line: There is moderate evidence that early sport specialization is associated with lower HRQOL compared with late sport specialization. It is important to educate athletes, parents, and coaches on the potential detriments that are associated with early sport specialization to allow stakeholders to make informed decisions regarding participation. Strength of Recommendation : Grade B evidence exists to support the idea that early, intensive sport specialization may be associated with decreased HRQOL in current college athletes.

Clinicians utilize instrument-assisted soft tissue mobilization (IASTM) to identify and treat myofascial dysfunction or pathology. Currently, little is known regarding the ability of clinicians to provide similar IASTM forces across treatment sessions. The authors’ purpose was to quantify clinician reliability of force application during a simulated IASTM treatment scenario. Five licensed athletic trainers with previous IASTM training (mean credential experience = 5.2 [4.3] y; median = 5 y) performed 15 one-handed unidirectional sweeping strokes with each of the 3 instruments on 2 consecutive days for a total of 90 data points each. The IASTM stroke application was analyzed for peak normal forces (F _peak) and mean normal forces (F _mean) by stroke across 2 sessions. The authors’ findings indicate IASTM trained clinicians demonstrated sufficient F _peak and F _mean reliability across a treatment range during a one-handed IASTM treatment. Future research should examine if IASTM applied at different force ranges influences patient outcomes.