The relationship between the blood pressure responses to exercise following training and detraining periods.

BACKGROUND: Exercise training lowers blood pressure (BP), while BP increases and returns to pre-training values with detraining. Yet, there is considerable variability in these BP responses. We examined the relationship between the BP responses after 6 months of training followed by 2 weeks of detraining among the same people. METHODOLOGY/PRINCIPAL FINDINGS: Subjects (n = 75) (X+SD, 50.2 ± 10.6 yr) were sedentary, obese, and had prehypertension. They completed an aerobic (n = 34); resistance (n = 28); or aerobic + resistance or concurrent (n = 13) exercise training program. We calculated a metabolic syndrome z score (MetSz). Subjects were classified as BP responders (BP decreased) or non-responders (BP increased) to training and detraining. Linear and multivariable regression tested the BP response. Chi Square tested the frequency of responders and non-responders. The systolic BP (SBP, r =  -0.474) and diastolic (DBP, r =  -0.540) response to training negatively correlated with detraining (p<0.01), independent of modality (p>0.05). Exercise responders reduced SBP 11.5 ± 7.8 (n = 29) and DBP 9.8 ± 6.2 mmHg (n = 31); non-responders increased SBP 7.9.± 10.9 (n = 46) and DBP 4.9 ± 7.1 mmHg (n = 44) (p<0.001). We found 65.5% of SBP training responders were SBP detraining non-responders; while 60.9% of SBP training non-responders were SBP detraining responders (p = 0.034). Similarly, 80.6% of DBP training responders were DBP detraining non-responders; while 59.1% of DBP training non-responders were DBP detraining responders (p<0.001). The SBP detraining response (r =  -0.521), resting SBP (r =  -0.444), and MetSz (r = 0.288) explained 44.8% of the SBP training response (p<0.001). The DBP detraining response (r =  -0.553), resting DBP (r =  -0.450), and MetSz (r = 0.463) explained 60.1% of the DBP training response (p<0.001). CONCLUSIONS/SIGNIFICANCE: As expected most subjects that decreased BP after exercise training, increased BP after detraining. An unanticipated finding was most subjects that increased BP after exercise training, decreased BP after detraining. Reasons why the negative effects of exercise training on BP maybe reversed with detraining among some people should be explored further. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov 1R01HL57354; 2003-2008; NCT00275145.

Duke Scholars

Author William Erle Kraus Medicine, Cardiology