Comparison of Trunk Muscle Activity Between Traditional Plank Exercise and Plank Exercise With Isometric Contraction of Ankle Muscles in Subjects With Chronic Low Back Pain

Electromyographic Comparison of an Abdominal Rise on a Ball with a Traditional Crunch

We propose a new exercise, the abdominal rise on the ball, to replace the traditional crunch in exercise programs. The aim of this study is to compare the activity of the abdominal muscles when performing an ARB with the same activity when performing a traditional crunch. Twenty healthy adults participated in the study. Surface electromyography (EMG) was recorded from the upper and lower rectus abdominis (URA, LRA), internal oblique (IO), external oblique (EO), transversus abdominis (TrA), and erector spinae (ES). EMG values were normalized to maximal voluntary isometric contraction. A paired t-test, nonparametric Wilcoxon test and correlation coefficient were used for statistical analysis. The normalized EMG values of EO, TrA and ES, were statistically significantly higher during the abdominal rise on the ball compared to the traditional crunch, while URA, LRA and IO were significantly lower during the abdominal rise on the ball compared to the traditional crunch. TrA, EO and IO are sufficiently activated during an abdominal rise on a ball, so the exercise could be deemed effective for strengthening these muscles.

Effects of High Intensity Plank Exercise on Physical Fitness and Immunocyte Function in a Middle-Aged Man: A Case Report

Background and Objectives: Although the plank exercise is difficult to perform for untrained people, it does not require money, special equipment, or much space. However, it is not known how plank exercises affect physical fitness and immunocyte function. This study analyzed the changes in physical fitness and immune cells of a middle-aged man after performing 4 weeks of elbow plank exercise. Materials and Methods: Elbow plank exercise was performed for approximately 20 min (resting time, around 10 min) a day, 5 days a week for 4 weeks. The intensity was checked daily with ratings of perceived exertion (RPE). When the participant reached an intensity of RPE 15, RPE 16, and RPE 17 of the RPE 20 scale, 1 min of rest was given before repeating the process. Results: Compared with the pre-values, (1) all the physical fitness factors (muscle strength, muscle endurance, flexibility, and cardiopulmonary fitness) were increased after 4 weeks; (2) body weight, skeletal muscle mass, and the basal metabolic rate were increased, whereas body fat mass and fat percentage were decreased; and (3) although the variables of complete blood count were changed positively, some were not. Specifically, CD3, CD8, and CD56 were increased, whereas CD4, CD4/CD8, and cytotoxicity were decreased. These results show that elbow plank exercise can improve all factors of physical fitness and improve some of the immunocyte functions of a middle-aged man. Conclusions: This study confirmed that, although the elbow plank exercise of vigorous intensity for 4 weeks improved physical fitness, it was not effective in improving some immunocyte functions. Therefore, the exercise intensity of plank exercises for improving immunocyte functions should be reconsidered.