Uitwerking van ’n intensiewe afrigtingsprogram op die kardiostresindeks

Abstract

Rekrute in die gewapende magte word met talle stressors gekonfronteer, onder meer ’n strawwe opleidingsprogram wat ’n impak op hul fisiologiese funksionering kan hê. Die kardiostresindeks (KSI) is ’n nie-indringende merker van die stres wat die hart ervaar. Die berekening van die KSI is gebaseer op die duur van vaskulêre eksitasie (duur van QRS), hartkloptempo, hartritme en die standaardafwyking van die tyd wat verloop tussen elke opeenvolgende kardiale siklus (RRinterval). Die doel van die huidige studie was om die fisiologiese impak van 20 weke van strawwe opleiding op rekrute te toets, met behulp van KSI as ’n nie-indringende biomerker van kardiostres. Proefnemings is by drie geleenthede tydens die basiese militêre opleiding van rekrute, tussen die ouderdomme van 18 en 24 jaar, in die gewapende magte onderneem (week 1, week 12 en week 20) (n = 202, manlik = 115, vroulik = 87). Veranderlikes wat gemeet is, het die volgende ingesluit: rustende KSI, hartkloptempo (HKT) en bloeddruk. Data-analise is uitgevoer deur middel van gepaarde t-toetse ten einde die volgende pare te vergelyk: week 1 (basislyn) met week 12; week 12 met week 20; en week 1 met week 20. Wat die manlike rekrute betref, was die gemiddelde KSI en harttempo by al drie toetse binne normale perke. Die basislynwaardes vir vroulike rekrute was in betekenisvolle mate hoër in die eerste week. Daar was ’n algehele afname van die KSI oor die hele tydperk van 20 weke. Uit hierdie studie wil dit voorkom asof die meting van die KSI ’n nieindringende metode is om die uitwerking van afrigting op die hart te bepaal.

Armed service recruits are faced with many stressors, including a strenuous training regimen that may have an impact on their physiological functioning. The Cardio Stress Index (CSI) is a noninvasive marker of the stress that the heart is experiencing. The aim of the study was to test the physiological impact of 20 weeks of intense training of armed service recruits, using CSI as a noninvasive biomarker of cardiac stress. Armed service recruits are faced with many stressors, including a strenuous training regimen that may have an impact on their physiological functioning. The CSI is a noninvasive marker of the stress that the heart is experiencing. The calculation of the CSI is based on the duration of vascular excitation (QRS duration), heart rate, heart rhythm and standard deviation of the duration of time between each successive cardiac cycle (RR-interval). The aim of the present study was to test the physiological impact of 20 weeks of strenuous training of armed service recruits, using CSI as a noninvasive biomarker of cardiac stress. Experiments were conducted at three points in time (weeks 1, 12, 20) during the basic military training of armed service recruits (n = 202, males = 115, females = 87), aged between 18 and 24 years. Variables measured include: Resting CSI, heart rate and blood pressure. Data analysis was performed, using paired t-tests for pairwise comparisons of week 1 (baseline) with week 12; week 12 with week 20; and week 1 with week 20. The average CSI and heart rate remained within normal values for male participants on all three testing occasions. However, baseline readings for females were significantly higher during week 1. There was an overall decrease in the CSI in the 20 week time frame. From this study it seems as if the CSI measurement is a noninvasive method to establish the effects of training on the health of the heart.