Accelerated skeletal muscle wasting is a shared trait among many pathologies and aging. Acupuncture has been used as a therapeutic intervention to control pain; however, little is known about its effects on skeletal muscle atrophy and function. The study's purpose was to compare the effects of acupuncture, electro-acupuncture, and electrical stimulation on cast-induced skeletal muscle atrophy. Forty female Sprague Dawley rats were randomly divided into groups: Control, casted (CAST), CAST+Acupuncture (CAST-A), 4) CAST+Electro-acupuncture (CAST-EA), and CAST+Electrical stimulation (CAST-ES) (n = 8). Plaster casting material was wrapped around the left hind limb. Acupuncture and electro-acupuncture (10 Hz, 6.4 mA) treatments were applied by needling acupoints (stomach-36 and gallbladder-34). Electrical stimulation (10 Hz, 6.4 mA) was conducted by needling the lateral and medial gastrocnemius muscles. Treatments were conducted for 15 min, three times/week for 14 days. Muscle atrophy F-box (MAFbx), muscle RING finger 1 (MuRF1), and contractile properties were assessed. Fourteen days of cast-immobilization decreased muscle fiber CSA by 56% in the CAST group (p = 0.00); whereas, all treatment groups demonstrated greater muscle fiber CSA than the CAST group (p = 0.00). Cast-immobilization increased MAFbx and MuRF1 protein expression in the CAST group (p<0.01) while the CAST-A, CAST-EA, and CAST-ES groups demonstrated lower levels of MAFbx and MuRF1 protein expression (p<0.02) compared to the CAST group. Following fourteen days of cast-immobilization, peak twitch tension did not differ between the CAST-A and CON groups (p = 0.12). Skeletal muscle atrophy, induced by 14 days of cast-immobilization, was significantly attenuated by acupuncture, electro-acupuncture, or electrical stimulation.

Field lacrosse requires sudden directional changes and rapid acceleration/deceleration. The capacity to perform these skills is dependent on explosive muscle force production. Limited research exists on the potential of sprint interval training (SIT) to impact explosive muscle force production in field lacrosse players. The purpose of this study is to examine SIT, concurrent to field-lacrosse-specific training, on the rate of torque development (RTD), contractile impulse, and muscle function in female high school field lacrosse players (n = 12; 16 ± 1 yrs.). SIT was performed three times per week, concurrent to field-lacrosse-specific training, for 12 weeks. Right lower-limb muscle performance was assessed pre-, mid-, and post-SIT training via isometric and isokinetic concentric knee extensor contractions. Outcomes included RTD (Nm·s⁻¹), contractile impulse (Nm·s), and peak torque (Nm). RTD for the first 50 ms of contraction improved by 42% by midseason and remained elevated at postseason (p = 0.004, effect size (ES) = −577.3 to 66.5). Contractile impulse demonstrated a training effect across 0–50 ms (42%, p = 0.004, ES = −1.4 to 0.4), 0–100 ms (33%, p = 0.018, ES = 3.1 to 0.9), and 0–200 ms (22%, p = 0.031, ES = −7.8 to 1.6). Isometric (0 rad·s⁻¹) and concentric (3.1 rad·s⁻¹) strength increased by 20% (p = 0.002, ES = −60.8 to −20.8) and 9% (p = 0.038, ES = −18.2 to 0.0) from SIT and field-lacrosse-specific training, respectively (p < 0.05). SIT, concurrent to field-lacrosse-specific training, enhanced lower-limb skeletal muscle performance, which may enable greater sport-specific gains.

As a sport, field lacrosse requires seamless transitions between acceleration and deceleration. Unfortunately, linear displacement variables at a constant speed underestimate the energy demand in team sports, as they fail to account for the additional energy expended during acceleration and deceleration. In order to address these additional energy costs and offer a more precise measure of an athlete's workload, the metric called metabolic equivalent distance (MED) was developed. The purpose of the study was to assess the differences in MED across game quarters and athlete positions among female collegiate lacrosse players and determine potential relationships between MED and other workload variables. Seventeen female collegiate lacrosse players wore global positioning systems units, and data were collected over the course of 17 games. Performance variables were analyzed per minute played (min PT) and included: MED (m), total distance (m), accelerations (count), decelerations (count), total sprints (count), metabolic peak power (J), metabolic energy cost (J/kg/m), and equivalent distance index (%). No difference was found between athlete position. Performance variables did not differ between game quarters, except for playing time (p < .001). Athlete playing time was reduced in the 3^rd and 4^th quarters compared to quarter 1 (p < .001). MED showed a perfect correlation with total distance and metabolic energy cost (r = 1; p < .001) and a near-perfect correlation with accelerations and total sprints (r = .93; p < .001). Decelerations exhibited a strong correlation with MED (r = .86; p < .001). MED was moderately correlated with metabolic peak power (r = .34; p < .001); whereas equivalent distance index displayed a small correlation (r = .15; p = .02). Athletes exhibited a consistent output in metabolic workload variables across position and game per minute of play. MED could serve as a surrogate workload variable to better understand the athlete’s energy expenditure during high-intensity training and game play.

The prevalence of skeletal muscle atrophy, caused by disease and aging, is rising as life expectancy increases. Exercise is the most effective treatment option; however, it is often impractical for individuals suffering from disease or bedridden. The formulation of non-exercise-based interventions is necessary. This study assessed the impact of acupuncture (AC), electro-acupuncture (EA), and electrical stimulation (ES) on muscle mass and contractile properties in a model of casting-induced muscle atrophy. Sprague-Dawley rats (n = 40) were assigned to five groups: control (CON), cast (CT), cast receiving AC (CT-AC), cast receiving EA (CT-EA), and cast receiving ES (CT-ES) (n = 8 each). Treatments were 15 min and three times/week for 14 days. Contractile properties and protein markers of atrophy and inflammation were measured. Casting decreased muscle mass and fiber cross-sectional area, but AC, EA, and ES attenuated cast-induced muscle atrophy. All treatments increased peak twitch tension compared to CT. CT increased the protein levels of MAFbx and MuRF1, while AC, EA, and ES mitigated the elevation of these proteins. Our results indicate that acupuncture, electro-acupuncture, and electrical stimulation show promise as therapeutic strategies to counteract skeletal muscle loss and dysfunction resulting from disuse atrophy caused by injury, disease, and aging.

This study analyzed the differences by position in acceleration, deceleration, and the ratio of accelerations to decelerations in drills and quarters of games (Q1-Q4). Data were collected in 23 female collegiate lacrosse athletes (20.8 ± 1.5 years, 168.3 ± 6.1 cm), consisting of ten midfielders, five defenders, and eight attackers. Drills were categorized as: stickwork (SW), small-sided games (SSG), warm-up (WU), active recovery (AR), individual skills (IS), scrimmage, and conditioning. AR (0.31 ± 0.09 accelerations/min) and WU (0.47 ± 0.07 accelerations/min) showed the lowest number of accelerations, and conditioning and SW were the highest (>1.0 accelerations/min). Conditioning showed the highest demand for decelerations (0.37 ± 0.14 decelerations/min) and AR and WU had the fewest (0.10 ± 0.04 decelerations/min). AR, IS, SW, and WU all had higher acceleration/deceleration ratios (4:1 to 5.7:1) than the remaining drill types (p = .000 - .050, 3:1-4:1). Q1 had a higher acceleration demand (0.72 ± 0.52 accelerations/minute) than the remaining three quarters (0.57 - 0.67 accelerations/min). The game demand in decelerations was approximately 0.20 decelerations/minute across all quarters and the acceleration/deceleration ratio was approximately 4:1, with the exception of defenders in Q1 who had 6:1 ratio. There is a large demand for accelerations in field lacrosse with no positional differences, and training should be devoted towards this skill.