Date of Award

2022

Degree Name

Exercise Science

College

College of Health Professions

Type of Degree

M.S.

Document Type

Thesis

First Advisor

Robert O. Powell, PhD, Committee Chair

Second Advisor

Nalini Santanam, PhD, MPH, Committee Member

Third Advisor

Kumika Toma, PhD, Committee Member

Abstract

Exercise has long been established as a therapeutic modality to improve health and related physical fitness, sports performance, and injury/risk reduction in both adults and adolescents (Haff & Triplett, 2015; Kaminsky, 2010). Nonetheless, there is a lack of research investigating the negative effects of exercise overstress (i.e., overtraining syndrome) in these populations, particularly adolescents (Brenner & American Academy of Pediatrics Council on Sports Medicine and Fitness, 2007; Matos & Winsley, 2007). The objective of this study was to examine hormone biochemical markers, anthropometric markers, and behavioral traits, which are associated with overtraining syndrome, in adolescent C57BL/6 mice. A total of 24 mice were randomly assigned to three groups in this study (sedentary group, moderately-trained exercise group, and overtrained exercise group; n=8 mice per group) during an eight-week intervention. Primary assessments were conducted at baseline, mid, and post-intervention and included the hormones: corticosterone and IGF-1 as well as body composition measures using MRI. Behavioral measures included weekly food consumption using a digital scale, edge time and center time using open field apparatus and Any-maze software. Baseline values for hormone concentrations, anthropometrics (body composition) and behavior of each group were the same, respectively with the exception of precent lean mass which displayed a significant difference between Overtrained and Sedentary groups (p= 0.034059). Following the intervention, there was a significant difference in plasma corticosterone concentrations across time between Overtrained and Sedentary groups (p=0.0022) as well as Overtrained and Moderate Trained groups (p=0.0098). The Overtrained group displayed the highest levels of corticosterone concentrations in ng/ml (153.09 ± 99.92) among all groups post-study time point (8 weeks). IGF-1 results showed no significant differences among groups across time (p=0.9754); however, time was significant, and all groups decreased in IGF-1 levels across time (p=0.0168). Food consumption results showed significantly different group interactions (p<0.0001) with the Overtrained group displaying the greatest amount of food consumed among all groups between weeks four-eight (132g-183g). In conclusion, the results of this study contribute to the literature regarding the exercise stress response in adolescent mice with physical overstress demonstrating greater negative responses to overtraining variables. Further research is necessary to better understand overtraining syndrome in adolescents, what biomarkers need assessed, and their implications to determine clinical relevance to physicians, coaches, parents and exercise specialists alike to recognize and reduce overtraining syndrome. ><0.0001) with the Overtrained group displaying the greatest amount of food consumed among all groups between weeks four-eight (132g-183g). In conclusion, the results of this study contribute to the literature regarding the exercise stress response in adolescent mice with physical overstress demonstrating greater negative responses to overtraining variables. Further research is necessary to better understand overtraining syndrome in adolescents, what biomarkers need assessed, and their implications to determine clinical relevance to physicians, coaches, parents and exercise specialists alike to recognize and reduce overtraining syndrome.

Subject(s)

Exercise – Health aspects.

Biochemical markers.

Biometric identification.

Stress (Physiology) – Exercise.

Teenagers -- Exercise.

Adulthood – Exercise.

Download

Share

COinS