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The Relationship Between Exposure to Cumulative Trauma and Heart Rate Variability Recovery After Performing Aerobic Exercise
Objective: Existing literature supports a relationship between exposure to cumulative trauma and its impact on autonomic function. One way to detect a potential disturbance in cardiac autonomic function is to examine the heart's activity, which can be done by examining the variation in time intervals between adjacent heart beats, known as heart rate variability. The autonomic nervous system is also responsible for controlling physiological changes in the body during exercise. Little research has been done regarding how the exposure to cumulative trauma can potentially influence the time it takes for heart rate and heart rate variability to recover after exercise. This information can be of value when assessing cardiovascular health and fitness since it can help experts in the field prescribe proper exercise intensities and avoid putting the client at risk for exercise related complications. The purpose of the proposed study is to examine the impact exposure to cumulative trauma may have on heart rate variability and heart rate recovery following maximal aerobic exercise. Methods: 50 students at California State University, Northridge, performed maximal aerobic exercise on a cycle ergometer, using an incremental test protocol. The participants were equipped with the Vivometrics Lifeshirt in order to measure heart rate variability and heart rate recovery prior to, during, and after maximal aerobic exercise. The heart rate variability parameters of interest were the standard deviation of N-N intervals (SDNN), and the root mean square of successive differences between normal heart beats (RMSSD). To evaluate cumulative trauma, anxiety, and depression, the following psychometric instruments were used: Traumatic Events Questionnaire (TEQ), Adverse Childhood Experience (ACE), Posttraumatic Stress Diagnostic Scale (PDS), Beck Anxiety Inventory (BAI), and the Beck Depression Inventory instrument (BDI). A group of participants with no previous exposure to trauma were enrolled in the control group. Results: It is anticipated that exposure to cumulative trauma will be associated with an elevated heart rate during recovery when compared to baseline measures at minutes one and five of active recovery (pedaling against zero resistance) after maximal aerobic exercise. It is also anticipated that exposure to cumulative trauma will be associated with a lesser recovery in SDNN and RMSSD when comparing baseline measures to active recovery (pedaling against zero resistance), at minute one and five post maximal aerobic exercise. In addition, it is anticipated that exposure to cumulative trauma will be related to a higher recovery heart rate, and a reduced recovery in SDNN and RMSSD, when comparing baseline values to those obtained during the three minutes of seated rest subsequent to the five minutes of active recovery. Conclusion: The anticipated results indicate that exposure to cumulative trauma can be associated with a lesser recovery in heart rate, RMSSD, and SDNN after maximal aerobic exercise.