A Comparison of Muscle Activation Among the Front Squat, Overhead Squat, Back Extension and Plank

International Journal of Exercise Science 13(1): 714-722, 2020. The purpose of this study was to compare the muscle activation of the scapula, leg, and trunk among the front squat (FS), overhead squat (OHS), back extension (BE) and plank (PL). Seven recreationally trained men (age: 28 ± 3.6 years, body mass: 92 ± 26.1 kg, height: 175 ± 5.3 cm, 3-RM front squat test: 125 ± 49.8 kg, 3-RM overhead squat test: 91 ± 15.5 kg) participated in this within-subject crossover design. Two isometric exercises (plank and Biering-Sorenson back extension) were also included for trunk musculature comparisons. Neuromuscular activitation of the vastus lateralis (VL), biceps femoris (BF), thoracic region of erector spinae (ES), middle trapezius (MT), rectus abdominis (RA), external oblique (EO), serratus anterior (SA), and anterior deltoid (AD). The neuromuscular activity of the FS and OHS were analyzed using a 2 X 3 (squat variation X intensity) repeated measures analysis of variance (ANOVA). Effects were further analyzed by Bonferroni corrected paired t-tests. Results showed that AD activity was significantly greater (p \u3c .05) during the FS compared to OHS at 65 and 95% of the 3-RM, while MT activity was significantly greater (p \u3c .05) during the OHS than the FS at 80 and 95% of the 3-RM. ES activity was significantly greater (p\u3c .05) during both the FS and OHS compared to the BE, but PL elicited significantly greater EO and RA activity than both the FS and OHS. These findings reveal that the FS and OHS can help facilitate the activation of muscles supporting the shoulder complex, scapula and lower back

Measuring the Biomechanics and Energetics of Curved vs. Traditional Treadmills in Female Adults

Manufacturers claim that exercising on a curved treadmill will promote, proper running mechanics and up to 30% more calories compared to a traditional motorized treadmill. If the curved treadmill is able to increase metabolic costs while minimizing load on the user, it may prove to be beneficial to all populations. Exercising on a compliant, curved surface may prove to be especially beneficial to special populations where the onset of pain limits the duration of cardiovascular exercise. If the curved treadmill can minimize joint stress, it may prolong the length of time that someone with special considerations may be able to exercise. PURPOSE: The purpose of this study is to examine whether a non-motorized curved (aka curved) treadmill will provide a biomechanical or energetic advantage compared to a motorized flat (aka traditional) treadmill. We hypothesize that, when compared to the traditional motorized treadmill, the non-motorized treadmill will result in 1) significantly higher caloric expenditure and VO2% value and a 2) significant increase in forward trunk flexion under all testing conditions. METHODS: Participants wore a breathing mask connected to the Oxycon Mobile system to measure the metabolic cost of all each movement pattern. Additionally, participants were outfitted with reflective markers in order to capture 3-dimensional kinematic data. Participants were instructed to perform at their self-selected pace and afterwards randomly instructed to change speed to 15% above, and 15% below their self-selected walking and running pace. In total, there were four 15-minute blocks of exercise, each of which were separated by a 10-minute block of rest to ensure adequate recovery. RESULTS: There was not a significant increase in the amount of trunk flexion under any of the conditions between the curved and traditional treadmill. There was a significant increase in the amount of energy expenditure from the traditional treadmill to the curved treadmill. CONCLUSION: While still largely uninvestigated, curved treadmills are becoming more popular as a modality of cardiovascular exercise. Our findings suggest that female athletes may benefit from using curved treadmills over traditional treadmills because of the increased caloric expenditure and aerobic capacity but further research needs to be conducted in order to assess the viability as a safe option with respect to musculoskeletal structures