Stephanie Santana Pinto

Echo intensity is associated with skeletal muscle power and cardiovascular performance in elderly men

The purpose of the present study was to investigate the relationship between echo intensity, neuromuscular and cardiorespiratory performances in the elderly. Thirty-one healthy elderly men (65.5±5.0) participated in this study. Echo intensity of rectus femoris and quadriceps femoris muscle thicknesses was determined by ultrasound images. Lower-body isometric and isokinetic peak torques (60, 180 and 360°(.s-1)), as well as rate of force development were evaluated as strength parameters. In addition, torque per unit of muscle mass was evaluated by the quotient between isometric peak torque of the knee extensors and the quadriceps femoris muscle thickness. The peak oxygen uptake (VO(2peak)), maximum aerobic workload (W(máx)), absolute (VT(1) and VT(2)) ventilatory thresholds, as well as workloads at VT(1) and VT(2) (W(VT1) and W(VT2)) were evaluated during a maximal incremental test on a cycle ergometer. There were significant negative correlations between the individual values of echo intensity with the corresponding individual values of isometric and isokinetic peak torques (60, 180 and 360°(.s-1)) (r=-0.48 to r=-0.64; P<0.05), as well as with W(VT1) (r=-0.46) and W(VT2) (r=-0.50) (P<0.05). In addition, significant positive correlations were observed between torque per unit of muscle mass and cardiovascular parameters (r=0.52 to r=0.60; P<0.001). The present results suggest that the echo intensity analysis using computer-aided gray-scale analysis is a low cost, easily accessible, and a safe method to evaluate the muscle quality, and may contribute to the research of neuromuscular and cardiovascular performances in the elderly.

Physiological effects of concurrent training in elderly men.

The aim of the present study was to investigate the effects of concurrent strength and endurance training on neuromuscular and hormonal parameters in elderly men. 23 healthy men (65±4 years) were randomly assigned to 1 of 3 groups: concurrent (CG, n=8), strength (SG, n=8) or endurance group (EG, n=7). The programs consisted, of strength training, endurance training on a cycle ergometer or a combination of both in the same session 3 times per week over a duration of 12 weeks. Subjects were evaluated on parameters related to muscle strength, muscle activation and serum hormones. There were significant increases in lower-body strength in all groups (P<0.05), with higher increases in SG (67%) than CG (41%) and both were higher than EG (25%) (p<0.01). Only SG and CG increased upper-body strength (p<0.01), with no significant difference between the 2 groups. Furthermore, there were significant decreases in free testosterone in EG after training. Significant increases in isometric strength and maximal muscle activation (p<0.05) as well as decreases in the submaximal muscle activation to the same load, were only seen in SG (p<0.05). The present results suggest that the interference effect observed due to concurrent strength and endurance training could be related to impairment of neural adaptations.

Effects of Strength, Endurance, and Concurrent Training on Aerobic Power and Dynamic Neuromuscular Economy in Elderly Men

Cadore, EL, Pinto, RS, Pinto, SS, Alberton, CL, Correa, CS, Tartaruga, MP, Silva, EM, Almeida, APV, Trindade, GT, and Kruel, LFM. Effects of strength, endurance, and concurrent training on aerobic power and dynamic neuromuscular economy in elderly men. J Strength Cond Res 25(3): 758-766, 2011-The aim of this study was to investigate the effects of concurrent training on endurance capacity and dynamic neuromuscular economy in elderly men. Twenty-three healthy men (65 ± 4 years) were divided into 3 groups: concurrent (CG, n = 8), strength (SG, n = 8), and aerobic training group (EG, n = 7). Each group trained 3 times a week for 12 weeks, strength training, aerobic training, or both types of training in the same session. The maximum aerobic workload (Wmax) and peak oxygen uptake (&OV0312;O2peak) of the subjects were evaluated on a cycle ergometer before and after the training period. Moreover, during the maximal test, muscle activation was measured at each intensity by means of electromyographic signals from the vastus lateralis (VL), rectus femoris (RF), biceps femoris long head, and gastrocnemius lateralis to determine the dynamic neuromuscular economy. After training, significant increases in &OV0312;O2peak and Wmax were only found in the CG and EG (p < 0.05), with no difference between groups. Moreover, there was a significant decrease in myoelectric activity of the RF muscle at 50 (EG), 75 and 100 W (EG and CG) and in the VL for the 3 groups at 100 W (p < 0.05). No change was seen in the electrical signal from the lateral gastrocnemius muscle and biceps femoris. The results suggest specificity in adaptations investigated in elderly subjects, because the most marked changes in the neuromuscular economy occurred in the aerobically trained groups.

Neuromuscular economy, strength, and endurance in healthy elderly men.

Cadore, EL, Pinto, RS, Alberton, CL, Pinto, SS, Lhullier, FLR, Tartaruga, MP, Correa, CS, Almeida, APV, Silva, EM, Laitano, O, and Kruel, LFM. Neuromuscular economy, strength, and endurance in healthy elderly men. J Strength Cond Res 25(4): 997-1003, 2011-Declines in muscular strength resulting from reduced neural activity may influence the reduction in aerobic capacity in older men. However, there has been little investigation into the relationship between muscular strength and economy of movement during aerobic exercise in elderly subjects. Thus, the purpose of this study was to investigate the possible relationship between strength, aerobic performance, and neuromuscular economy in older men. Twenty-eight aged men (65 ± 4 years old) were evaluated in dynamic (1 repetition maximum test), isometric strength (maximal voluntary contraction), and rate of force development. Peak oxygen uptake, maximal workload, and ventilatory threshold were determined during a ramp protocol on a cycle ergometer. Throughout the same protocol, the neuromuscular economy (electromyographic signal) of the vastus lateralis was measured. Significant correlations were found between muscular strength, cardiorespiratory fitness, and neuromuscular economy (r = 0.43-0.64, p < 0.05). Our results suggest that cardiorespiratory capacity and economy of movement are associated with muscular strength during aging.

Vertical ground reaction force during water exercises performed at different intensities.

The aim of the present study was to compare the peak vertical ground reaction force (V-GRF(peak)) and impulse of women performing water aerobic exercises at different intensities in aquatic and dry land environments. 15 young women performed 1 session in each environment consisting of 3 water aerobic exercises (stationary running, frontal kick and cross country skiing) performed at 3 cadences (first ventilatory threshold, second ventilatory threshold and maximum effort, as determined during exercise in water) in a randomized order. 2-way and 3-way repeated measures ANOVA were used to analyze the impulse and V-GRF(peak), respectively. Significantly lower values of V-GRF(peak) and impulse (p<0.001) were observed for the aquatic environment. Significant differences were observed among all cadences for V-GRF(peak) and impulse (p<0.001) in both environments except for the V-GRF(peak) between the cadences corresponding to the second ventilatory threshold and maximum effort in the aquatic environment. In addition, significantly lower V-GRF(peak) values in the aquatic environment were found for cross country skiing compared to the other exercises (p<0.001). Thus, water exercises are safe for people that need to minimize vertical ground reaction force; however, an important issue to be considered during water aerobics training is the exercise and intensity to be prescribed.

Concurrent Training with Different Aerobic Exercises

The aim of the present study was to compare the effects of using different intensities and types of aerobic exercise (i. e., cycle ergometer or running) during concurrent training on neuromuscular adaptations. A total of 44 young women were randomly assigned to 1 of 4 groups: concurrent strength and continuous running training (SCR, n=10), concurrent strength and interval running training (SIR, n=11), concurrent strength and continuous cycle ergometer training (SCE, n=11), or strength training only (STO, n=12). Each group trained twice a week during 11 weeks. The following strength measurements were made on all subjects before and after training period: maximal strength (1RM) in knee extension, bench press and leg press exercises; local muscular endurance (number of repetitions at 70% of 1 RM) in knee extension and bench press exercises; and isometric and isokinetic peak torque of knee extension. There were significant increases in the upper and lower-body 1 RM, isometric and isokinetic peak torque in all training groups (p<0.001), with no differences between groups. The present results suggest that in young women, concurrent training performed twice a week promotes similar neuromuscular adaptations to strength training alone, regardless of the type and the intensity in which the aerobic training is performed.

Effects of intra-session exercise sequence during water-based concurrent training.

The aim was to investigate the effects of the intra-session exercise order during water-based concurrent training on the neuromuscular adaptations in young women. 26 women (25.1±2.9 years) were placed into 2 groups: resistance prior to (RA) or after (AR) aerobic training. Subjects performed resistance (sets at maximal effort) and aerobic training (exercises at heart rate corresponding to the second ventilatory threshold) twice a week over 12 weeks, performing both exercise types in the same training session. Upper (elbow flexion) and lower-body (knee extension) one-repetition maximum test (1RM) and peak torque (PT) were evaluated. The muscle thickness (MT) of upper (sum of MT of biceps brachii and brachialis) and lower-body (sum of MT of vastus lateralis, vastus medialis, vastus intermedius, and rectus femoris) was determined by ultrasonography. Moreover, the maximal electromyographic activity (EMG) of upper (biceps brachii) and lower-body (sum of EMG of vastus lateralis and rectus femoris) was measured. Both RA and AR groups increased the upper and lower-body 1RM and PT, while the lower-body 1RM increases observed in the RA was greater than AR (43.58±14.00 vs. 27.01±18.05%). RA and AR showed MT increases in all muscles evaluated, while the lower-body MT increases observed in the RA were also greater than AR (10.24±3.11 vs. 5.76±1.88%). There were increases in the maximal EMG of upper and lower-body in both RA and AR, with no differences between groups. Performing resistance prior to aerobic exercise during water-based concurrent training seems to optimize the lower-body strength and hypertrophy.

Correlation Between Rating of Perceived Exertion and Physiological Variables During the Execution of Stationary Running in Water at Different Cadences

Alberton, CL, Antunes, AH, Pinto, SS, Tartaruga, MP, Silva, EM, Cadore, EL, and Kruel, LFM. Correlation between rating of perceived exertion and physiological variables during the execution of stationary running in water at different cadences. J Strength Cond Res 25(1): 155-162, 2011-The purpose of the present study was to correlate the rating of perceived exertion (RPE) with cardiorespiratory and neuromuscular variables during the execution of stationary running in water at different cadences. The sample consisted of 12 apparently healthy women (age: 22.33 ± 0.57 years). During the assessment session, the subjects performed the stationary running exercise in water at 3 different cadences: 60, 80, and 100 bpm. The heart rate (HR), oxygen uptake (&OV0312;o2), ventilation (Ve), and electromyographic (EMG) signal of the vastus lateralis (VL), biceps femoris (BF), rectus femoris (RF), and semitendinosus (ST) muscles were measured during the exercise, and the overall body RPE was measured immediately following the end. Pearsons linear correlation and multiple linear regression were used, with p < 0.05. The analyses demonstrate a high and significant relationship between RPE and HR (r = 0.65; p < 0.001), RPE and %HR maximal (r = 0.65; p < 0.001), RPE and &OV0312;o2 (r = 0.60; p = 0.001), RPE and %&OV0312;o2 maximal (r = 0.71; p < 0.001), and RPE and Ve (r = 0.77; p < 0.001). However, there was no relationship between the RPE and the EMGs of the VL, BF, RF, and ST muscles. With regard to the regression, the model was significant (p < 0.001) with an r2 = 0.79, whereas the variables that explained better the RPE were %&OV0312;o2 maximal and Ve. Hence, these results suggest an association between the perception of exertion and cardiorespiratory variables, which was not the case with the neuromuscular variables evaluated in this study. Therefore, the Borg scale of RPE can be used when prescribing stationary running exercise in water for young women.

Cardiorespiratory and neuromuscular responses during water aerobics exercise performed with and without equipment.

The aim of the study was to compare the cardiorespiratory and neuromuscular responses to water aerobics exercise performed with and without equipment. 15 women performed stationary jogging combined with elbow flexion/extension without equipment, with water-drag forces equipment and with water-floating equipment, at 2 submaximal cadences and at maximal cadence. Heart rate, oxygen uptake and electromyographic signal from biceps brachii, triceps brachii, biceps femoris and rectus femoris were collected during the exercise. The heart rate and oxygen uptake showed significantly higher values during the execution of the water aerobics exercise with either equipment compared to the execution without equipment. In addition, significant difference was found between submaximal cadences. For neuromuscular responses, no significant differences were found between the submaximal cadences for all muscles analyzed; however, significant differences were found between these submaximal cadences and the maximal cadence. Similarly, the results showed no significant differences between the execution of the exercise with or without equipment, except in the muscle activation of triceps brachii and biceps femoris, which was higher when using water-floating and water-drag forces equipment, respectively. In conclusion, the water aerobics exercise presented higher cardiorespiratory responses with equipment and also increased the cadence of execution. Nevertheless, neuromuscular responses were higher only at maximal cadence.

MAXIMAL AND VENTILATORY THRESHOLDS OF OXYGEN UPTAKE AND RATING OF PERCEIVED EXERTION RESPONSES TO WATER AEROBIC EXERCISES

Abstract Alberton, CL, Antunes, AH, Beilke, DD, Pinto, SS, Kanitz, AC, Tartaruga, MP, and Kruel, LFM. Maximal and ventilatory thresholds of oxygen uptake and rating of perceived exertion responses to water aerobic exercises. J Strength Cond Res 27(7): 1897–1903, 2013—This study aimed to compare the V[Combining Dot Above]O2max and first and second ventilatory threshold (1stVT and 2ndVT) V[Combining Dot Above]O2 values and rating of perceived exertion (RPE) responses of treadmill running (TR) with those of 3 water aerobic exercises: stationary running (SR), jumping jack (JJ), and forward kick (FK). Nine women (22.89 ± 1.81 years, 1.66 ± 0.07 m, 58.46 ± 4.19 kg) performed 1 maximal test session for each of the 4 exercise protocols in a randomized order to determine the V[Combining Dot Above]O2max and V[Combining Dot Above]O2 values and RPE responses corresponding with the 1stVT and 2ndVT. V[Combining Dot Above]O2 values were also expressed as a percentage of V[Combining Dot Above]O2max (%V[Combining Dot Above]O2max). A repeated measures analysis of variance and Bonferroni’s post hoc test were used, with &agr; = 0.05 denoting statistical significance. The analyses showed that the V[Combining Dot Above]O2 responses were significantly higher for TR than for the other exercises at all effort intensities (V[Combining Dot Above]O2max: p < 0.001; 1stVT and 2ndVT V[Combining Dot Above]O2: p < 0.001), followed by intermediate responses for SR and FK and lower responses for JJ. However, no significant differences between exercises for values of %V[Combining Dot Above]O2max (1stVT: p = 0.099; 2ndVT: p = 0.131) and RPE (1stVT: p = 0.275; 2ndVT: p = 0.477) were found at submaximal intensities, indicating that it is possible to achieve and maintain the same training intensity with these exercises during a typical water fitness lesson. Moreover, the RPE values obtained for the 1stVT and 2ndVT can make the prescription of intensity for these water exercises for young women more simple and practical.