A Comparison of the Effects of Isotonic and Isokinetic Exercises on Leg Power

PROBLEM. The author has been interested in improving the jumping ability of the students and athletes with whom he has worked. Current literature reflects conflicting viewpoints concerning isokinetic training as a superior method to isotonic training for power development. It was the purpose of this study to determine if there is a difference between the effects of isotonic and isokinetic exercises on the leg power of men and women. PROCEDURE. Thirty-three Cedarville College students participated three days per week for five weeks in a training program for the cevelopment of leg power. The subjects were given the Vertical Power Jump test to assess their jumping abilities prior to training. On the bases of the pre-test scores and sex the subjects were divided into four groups . One group of men and one group of women trained on a Universal Gym leg press station. The other two groups trained on a Super Mini-Gym isokinetic device. Both groups did three sets of eight repetitions each training session. After the five-week training period the subjects were given the Vertical Power Jump test to determine the amount of change in leg power. FINDINGS. There were no significant differences in the amounts of change of the four groups. Gains in leg power were made by all of the groups. The biggest gain was made by the women\u27s isotonic group and the least gain was made by the women\u27s isokinetic group. CONCLUSIONS AND RECOMMENDATIONS. Isotonic and isokinetic exercises both caused improvement in the leg power of men and women over a five-week training period. There was no significant difference between the types of training used. The author recommends that a similar study be done with more subjects. He also suggests that a study be done comparing different types of isokinetic training programs with the number of repetitions, number of sets, frequency of training, and speed of the device as possible variables

John A. McGillivray

https://digitalcommons.cedarville.edu/oral_histories/1006/thumbnail.jp

Study Protocol for the COVID-19 Pandemic Adjustment Survey (CPAS): A Longitudinal Study of Australian Parents of a Child 0–18 Years

Background: The COVID-19 pandemic presents significant risks to the mental health and wellbeing of Australian families. Employment and economic uncertainty, chronic stress, anxiety, and social isolation are likely to have negative impacts on parent mental health, couple and family relationships, as well as child health and development. Objective: This study aims to: (1) provide timely information on the mental health impacts of the emerging COVID-19 crisis in a close to representative sample of Australian parents and children (0–18 years), (2) identify adults and families most at risk of poor mental health outcomes, and (3) identify factors to target through clinical and public health intervention to reduce risk. Specifically, this study will investigate the extent to which the COVID-19 pandemic is associated with increased risk for parents’ mental health, lower well-being, loneliness, and alcohol use; parent-parent and parent-child relationships (both verbal and physical); and child and adolescent mental health problems. Methods: The study aims to recruit a close to representative sample of at least 2,000 adults aged 18 years and over living in Australia who are parents of a child 0–4 years (early childhood, N = 400), 5–12 years (primary school N = 800), and 13–18 years (secondary school, N = 800). The design will be a longitudinal cohort study using an online recruitment methodology. Participants will be invited to complete an online baseline self-report survey (20 min) followed by a series of shorter online surveys (10 min) scheduled every 2 weeks for the duration of the COVID-19 pandemic (i.e., estimated to be 14 surveys over 6 months). Results: The study will employ post stratification weights to address differences between the final sample and the national population in geographic communities across Australia. Associations will be analyzed using multilevel modeling with time-variant and time-invariant predictors of change in trajectory over the testing period. Conclusions: This study will provide timely information on the mental health impacts of the COVID-19 crisis on parents and children in Australia; identify communities, parents, families, and children most at risk of poor outcomes; and identify potential factors to address in clinical and public health interventions to reduce risk