Background: An ambulatory 24-hour BP-monitoring (ABPM) is of paramount importance, while patients are engaged in their usual activities, for a better representation of blood pressure (BP). ABPM provides not only automated measurements of brachial-artery pressure over a 24-hour period but also a highly reproducible circadian profile. The purpose of this investigation was to evaluate the effect of strength training (ST) on BP in patients with type 2 diabetes mellitus (T2D) and to obtain new and important information on BP profiles over 24-hour by using an ABPM.
Material and methods: We recruited ten patients (mean age: 59.7 +/- 7.3) from our Diabetes Department who participated in a 4-month systematic ST program on three non-consecutive days of the week. The ST program consisted of exercises for all major muscle groups. The numbers of sets for each muscle group were systematically increased from 3 at the beginning of the program to 4, 5 and finally 6 sets per week at the end of the program. The ABPM equipment (oscillometric Model Mobil-O-Graph CE 0434) was applied before and after 4-month training period. Routine HbA1C levels were measured using standard techniques. All subjects took a cycling test to measure maximum oxygen uptake (VO2peak) and maximum workload (Wmax) before and after the training period. Maximal strength was determined by one repetition maximum (1RM) in kp for the bench press, bench pull and leg press exercises, using the Concept 2 Dyno.
Results: Analysis of the pooled daytime and night-time data showed a significant reduction of mean arterial BP (from 93.8 +/- 19.2 to 90.6 +/- 14.3 mmHg; p > 0.01) after a 4-month ST (-3.4% mmHg). VO2peak (p < 0.05), Wmax (p < 0.05), 1RM for all muscle groups (p < 0.01), lean body mass (p < 0.05) and percent body fat (p < 0.05) improved significantly after a 4-month of ST. HbA1C showed a significant reduction by 14.5% (from 8.3 +/- 1.7 to 7.1 +/- 0.9%; p < 0.01).
Conclusion: We found a significant reduction of mean arterial BP after a 4-month ST, measured by the ABPM system. These results demonstrate that ST may not only increase muscle strength but also decrease BP and perhaps the risk of future CVD development.