Strength and power training did not modify cardiovascular responses to aerobic exercise in elderly subjects

Abstract

Resistance training increases muscle strength in older adults, decreasing the effort necessary for executing physical tasks, and reducing cardiovascular load during exercise. This hypothesis has been confirmed during strength-based activities, but not during aerobic-based activities. This study determined whether different resistance training regimens, strength training (ST, constant movement velocity) or power training (PT, concentric phase performed as fast as possible) can blunt the increase in cardiovascular load during an aerobic stimulus. Older adults (63.9 ± 0.7 years) were randomly allocated to: control (N = 11), ST (N = 13, twice a week, 70-90% 1-RM) and PT (N = 15, twice a week, 30-50% 1-RM) groups. Before and after 16 weeks, oxygen uptake (VO 2 ), systolic blood pressure (SBP), heart rate (HR), and rate pressure product (RPP) were measured during a maximal treadmill test. Resting SBP and RPP were similarly reduced in all groups (combined data = -5.7 ± 1.2 and -5.0 ± 1.7%, respectively, P < 0.05). Maximal SBP, HR and RPP did not change. The increase in measured VO 2 , HR and RPP for the increment in estimated VO 2 (absolute load) decreased similarly in all groups (combined data = -9.1 ± 2.6, -14.1 ± 3.9, -14.2 ± 3.0%, respectively, P < 0.05), while the increments in the cardiovascular variables for the increase in measured VO 2 did not change. In elderly subjects, ST and PT did not blunt submaximal or maximal HR, SBP and RPP increases during the maximal exercise test, showing that they did not reduce cardiovascular stress during aerobic tasks.

Efeitos de longo prazo do treinamento resistido nos indicadores de obesidade: uma revisão sistemática

“…The interval between exercise series, cited in 11 studies, ranged from 30 seconds to 3 minutes, with no predominance of a specific interval (Table 2). Only two articles cited the speed of execution (2"X2") 11,18 (a result not shown in the table). In the specific case of TRT, the BMI values showed significant reductions in 2 articles 10,27 , while in 7 other articles 11,13,14,16,17,25,35 they were unchanged.…”

“…This variation in TRT studies may be explained by the fact that this training model does not permit aerobic exercise, which is a type of exercise that reduces the percentage of BF 18 , indicating that aerobic training is significantly better than TRT for the reduction of fat mass 25 . Analysis of BMI equivalent values revealed that in seven of the 16 TRT studies 11,13,14,16,17,25,35 the BMI did not change and in five 12,18,19,28,29 it increased. This behavior may be explained by the fact that TRT induces significant strength gains associated with muscle hypertrophy, which increase fat-free mass 18 .…”

“…Two studies used a time of one minute for the repetitions 13,27 . The percent load used, cited in 8 studies 11,12,17,[25][26][27]35,37 , ranged from 20 to 90% one repetition maximum (1 RM), with the interval of load intensity most frequently used being 50 to 80%. The interval between exercise series, cited in 11 studies, ranged from 30 seconds to 3 minutes, with no predominance of a specific interval (Table 2).…”

“…Eleven of the 17 studies were conducted on samples of 30 subjects or less [11][12][13][16][17][18][19]25,26,28,37 , a fact that may have generated imprecise estimates, explaining the absence of statistically significant results.…”

Cardiology in Brazilian scientific journals: an overview

“…Machado et al [30] investigated the behavior of heart rate and heart rate variability during different loads of resistance exercise (incline bench press) in ten patients with coronary artery disease vs. ten healthy sedentary controls and conclude that loads up to 30% one-repetitionmaximum during incline bench press, result in depressed vagal modulation in both groups, although only the coronary artery disease patients presented sympathetic overactivity at 20% one-repetition-maximum upper limb exercise. Kanegusuku et al [31] determined in 30 older adults whether different resistance training regimens, strength training (constant movement velocity) or power training (concentric phase performed as fast as possible) can blunt the increase in cardiovascular load during an aerobic stimulus and conclude that neither strength nor power training blunted submaximal or maximal heart rate, Systolic blood pressure or the rate-pressure product during the maximal exercise test, showing that they did not reduce cardiovascular stress during aerobic tasks. Mainenti et al [32] investigated the effects of levothyroxine on cardiopulmonary exercise reserve and recovery in 23 women with subclinical hypothyroidism submitted to two ergospirometry tests, with an interval of 6 months of normalization of thyroid-stimulating hormone levels (levothyroxine replacement group) or simple observation.…”