Marzo Edir Da Silva-Grigoletto

Effect of high-load and high-volume resistance exercise on the tensiomyographic twitch response of biceps brachii

The purpose of the present study was to assess the ability of TMG in detecting mechanical fatigue induced by two different resistance exercises on biceps brachii: high-volume (HV), and high-load (HL). Sixteen healthy subjects (age 25.1±2.6years; body mass 79.9±8.9kg; height 179±7.4cm) performed arm-curl in two different protocols (HV: 8×15×10kg, HL: 5×3×30kg). Tensiomyography was used to assess muscle response to both exercise protocols. The contractile capacity of biceps brachii significantly varied by means of the effects of potentiation and fatigue mechanisms that take place at different exercise phases. The most significant changes correspond to values of maximum radial displacement of muscle belly (D(m)), sustained contraction time (T(s)), relaxation time (T(r)), and contraction velocity (V(c)). The behavior of these parameters is, in general, similar in both exercise protocols, but they show subtle differences among them. During the first set, in both protocols, values for V(c) increase, along with a decrease in T(r), T(s), and D(m) values. Fatigue onset was evident from changes in such parameters, with HL being the first in showing these mechanisms. Tensiomyography has been shown to be highly sensitive in detecting fatigue-induced changes.

Acute and cumulative effects of different times of recovery from whole body vibration exposure on muscle performance.

Da Silva-Grigoletto, ME, Vaamonde, DM, Castillo, E, Poblador, MS, García-Manso, JM, and Lancho, JL. Acute and cumulative effects of different times of recovery from whole body vibration exposure on muscle performance. J Strength Cond Res 23(7): 2073-2082, 2009-This experiment was designed to assess the acute (Study I) and cumulative response (Study II) of muscle performance to differing recovery times after exposure to whole body vibration (WBV). All subjects (mean age 19.7 ± 1.9) were healthy and physically active. In both studies, subjects were exposed to a WBV bout of 6 exposures of 60 seconds each, with frequency of 30 Hz and amplitude of 4 mm. In Study I, subjects (n = 30) underwent 3 trials (1 per day) on different days with a 2-day wash-out period between trials; each trial included either a 1, 2, or 3 minutes of recovery between exposures to WBV. All subjects underwent all trials, which were randomly assigned. Jump ability and muscle power were measured before and after each bout. In Study II, subjects (n = 45) underwent 12 sessions of WBV training in 4 weeks (3 bouts/wk). The subjects were randomly assigned to 1 of the following 3 groups: WBV with 1-minute recovery periods between exposures, WBV with 2-minute recovery periods between exposures, or control group. Jump ability, muscle power, and strength were measured before and after each bout. In the acute study (I), recovery times of 1 and 2 minutes enhanced all measured parameters (p < 0.05), with the 2-minute recovery being more effective. In the long-term study (II), however, although both periods also enhanced the measured parameters (p < 0.05), the 1-minute recovery proved more effective because the response was modified by systematic stimulation. In conclusion, 2-minute recovery periods provided the most effective acute enhancement of muscle activation, whereas the 1-minute recovery provided a more effective cumulative enhancement of muscle power and jump ability.

Determining the optimal whole-body vibration dose–response relationship for muscle performance

Da Silva-Grigoletto, ME, de Hoyo, M, Sañudo, B, Corrales, L, and García-Manso, JM. Determining the optimal whole-body vibration dose–response relationship for muscle performance. J Strength Cond Res 25(12): 3326–3333, 2011—The aim of this investigation was twofold: first, to determine the optimal duration of a single whole-body vibration (WBV) exposure (phase 1) and second to find out the ideal number of sets per intervention to maximize muscle performance (phase 2). All participants were young (age: 19.4 ± 1.6 years), healthy, physically active men. In both studies, a 30-Hz frequency and a 4-mm peak-to-peak displacement were used. In phase 1, subjects (n = 30) underwent 3 sets of different durations (30, 60, and 90 seconds), whereas in phase 2, subjects (n = 27) underwent 3 interventions where the duration remained fixed at 60 seconds, and the number of sets performed (3, 6, or 9) was modified. The recovery time between sets was set at 2 minutes. In all interventions, each set consisted of 1 isometric repetition in a squat position with knees flexed at 100°. Before and after each session, jump height (countermovement jump [CMJ] and squat jump [SJ]) and power output in half squat (90° knee flexion) were assessed. In phase 1, an improvement in jump ability and power output was observed after the 30- and 60-second intervention (p < 0.01), whereas the 90 second intervention, participants just experienced a decrease in SJ and CMJ (p < 0.05). When comparing the different protocols, the greatest response was achieved using 60 seconds (p < 0.05), which was therefore considered as the optimal duration to be used in phase 2. In the second phase, improvements in jump ability and power output were found with 3 and 6 sets (p < 0.05), whereas with 9 sets, participants actually experienced a decrease in these variables. Intergroup comparison showed a greater effect for the program of 6 sets (p < 0.05). In conclusion, a WBV intervention consisting of six 60-second sets produces improved muscle performance measured by SJ, CMJ, and power output.

Effects of training exercises for the development of strength and endurance in soccer.

A training program designed to increase strength and aerobic endurance in 1 season was tested on 16 professional soccer players from Spain with a mean age of 28 ± 3.37 years. The schedule comprised 4 macrocycles of 12 weeks of aerobic endurance and strength training. As much for the strength training as for the aerobic endurance, the program used a sequence of general, special, and specific exercises. Assessments were made with routine tests (i.e., squat jumps [SJs], countermovement jumps [CMJs], and countermovement jumps with arm swing [CMJas]) at the end of each macrocycle, and the Probst test was used to assess aerobic endurance as a function of running speed and distance, at the start and end of the training schedule and at the start of the third macrocycle. Jumps were performed on an infrared platform fitted to the MuscleLab system. The Probst test showed differences between the first evaluation and the second and third evaluations: 3,550 ± 411.59 m vs. 2,006 ± 207.20 m (P < 0.01). For 2 of the 3 jumps analyzed, the results were better in the last 2 than in the first 2 evaluations (SJ, 43.13 ± 3.77 vs. 39.47 ± 3.4 [P < 0.05]; CMJ, 49.80 ± 3.77 vs. 46.67 ± 3.76 [P < 0.05]; CMJas, 56.24 ± 5.2 vs. 52.98 ± 4.54 [P > 0.05]). Improvement of aerobic endurance was produced on the first phase of the season as a consequence of the training. To increase strength, it is necessary to augment the number of training sessions of this type. It is convenient to separate aerobic endurance and strength training to create more ample blocks during the last 2 macrocycles.

Heart rate variability during high-intensity exercise

The aim of this paper is to describe and analyse the behaviour of heart rate variability (HRV) during constant-load, high-intensity exercise using a time frequency analysis (Wavelet Transform). Eleven elite cyclists took part in the study (age: 18.6±3.0 years; VO2max: 4.88±0.61 litres·min−1). Initially, all subjects performed an incremental cycloergometer test to determine load power in a constant load-test (379.55±36.02 W; 89.0%). HRV declined dramatically from the start of testing (p <0.05). The behaviour of power spectral density within the LF band mirrored that of total energy, recording a significant decrease from the outset LF peaks fell rapidly thereafter, remaining stable until the end of the test. HF-VHF fell sharply in the first 20 to 30 seconds. The relative weighting (%) of HF-VHF was inverted with the onset of fatigue, [1.6% at the start, 7.1 (p <0.05) at the end of the first phase, and 43.1% (p <0.05) at the end of the test]. HF-VHFpeak displayed three phases: a moderate initial increase, followed by a slight fall, thereafter increasing to the end of the test. The LF/HF-VHF ratio increased at the start, later falling progressively until the end of the first phase and remaining around minimal values until the end of the test.

Study of mechanical characteristics of the knee extensor and flexor musculature of volleyball players

Abstract The aim of the present study was to analyse differences in muscle response and mechanical characteristics of the vastus medialis, rectus femoris, vastus lateralis, and biceps femoris in elite volleyball players of both sexes using tensiomyography. To this end, 47 players of nine nationalities playing for teams in the mens and womens Spanish Superleagues were assessed. The sample comprised 22 women (age 24.6±4.3 years; weight 72.14±10.06 kg; height 178.40±8.50 cm) and 25 men (age 25.0±4.3 years; weight 88.76±9.07 kg; height 194.71±7.84 cm). Tensiomyography was used to assess muscular response and muscular mechanical characteristics. For this purpose, the following variables were analysed: maximum radial displacement of muscle belly and normalized response speed. The findings show, both in men and women, a higher normalized response speed score in the vastus lateralis and vastus medialis compared with the rectus femoris and biceps femoris. A marked lateral symmetry of maximum radial displacement of the muscle belly was also observed in the musculature of the lower limbs, with no statistically significant differences being detected in either men or women. There were, however, clear differences in terms of normalized response speed between male and female volleyball players: women displayed a more pronounced difference in the normalized response speed of the musculature responsible for extension (vastus medialis, rectus femoris, and vastus lateralis) and flexion (biceps femoris) of the knee joint than men. Moreover, tensiomyography proved to be a highly sensitive tool for detecting such changes.

Impact of an acute bout of vibration on muscle contractile properties, creatine kinase and lactate dehydrogenase response.

Abstract The aim of this study was to assess the effects of a bout of whole body vibration (WBV) on muscle response and to determine whether this stimulus leads to muscle damage. Thirty healthy and physically active participants (mean±SD; age: 21.8±2.0 years; height: 176.7±5.8 cm; body mass: 76±6.8 kg and BMI: 23.1±3.7 kg·m−2) participated in this study. Participants were randomly allocated in one of two groups, one of them performed a bout of 360 s WBV (frequency: 30 Hz; peak-to-peak displacement: 4 mm) (VIB) and the other one adopted a sham position (CON). Muscle contractile properties were analysed in the rectus femoris (RF) by using tensiomyography (TMG) 2 min before the warm-up and 2 min after intervention. Muscle damage was assessed by determining plasma creatine kinase (CK) and lactate dehydrogenase (LDH) levels at three time points; 5 min before warm-up and 1 h and 48 h after the intervention. TMG results showed a significant decrease in maximal displacement (p<0.05) and delay time (p<0.05) in VIB and in delay time (p<0.05) and relaxation time (p<0.05) in CON. Muscle damage markers showed significant group differences (p<0.05) for CK 1 h after the intervention. In addition, differences for CK 1 h after the intervention from baseline (p<0.05) were also observed in VIB. In conclusion, a 6-min bout of WBV results in an increase of muscle stiffness in RF and increased CK levels 1 h after intervention (returning to baseline within 48 h).

Pre-exercise Intake of Different Carbohydrates Modifies Ischemic Reactive Hyperemia After a Session of Anaerobic, But Not After Aerobic Exercise

Fernández, JM, Da Silva-Grigoletto, ME, Caballero-Villarraso, J, Gómez-Puerto, JR, Viana-Montaner, BH, Tasset-Cuevas, I, Túnez-Fiñana, I, Pérez-Martínez, P, López-Miranda, J, and Pérez-Jiménez, F. Pre-exercise intake of different carbohydrates modifies ischemic reactive hyperemia after a session of anaerobic, but not after aerobic exercise. J Strength Cond Res 24(6): 1623-1632, 2010-The acute ingestion of a supplement with different glycemic carbohydrates, including fructose, is a typical practice for athletes before exercising. Observational evidence suggests that different metabolic responses may modify the exercise-stimulated endothelium-dependent vasodilation. The purpose of the present study was to investigate whether endothelial reactivity, stimulated by anaerobic exercise (AnE) or aerobic exercise (AE), both performed with glycemic supplementation, is modified by the addition of fructose. Twenty physically trained men ingested an oral dose of glucose (G) or glucose plus fructose (F) 15 minutes before starting a 30-minute session of AnE (10 sets of 10 repetitions of half squat) or AE (cycling). The combination resulted in 4 randomized interventions in a crossover design in which all subjects performed all experimental conditions: G + AnE, F + AnE, G + AE, and F + AE. Ischemic reactive hyperemia (IRH), glycemia, plasma lipoperoxides (LPOs), nitric oxide (NO), and lactate were determined at baseline, exercise, and acute recovery time points. Immediately after AnE, IRH was 26.35% higher in F + AnE than in G + AnE (p < 0.05); this difference rose to 27.24% at the end of the recovery period (p < 0.05). The glycemic peak in F + AnE was lower than in G + AnE (p < 0.05), and there was a second peak during recovery (p < 0.05). There were no differences observed in LPO between anaerobic trials, but the NO bioavailability increased and was higher in F + AnE than in G + AnE after exercise and recovery (p < 0.05). Residual lactate was also higher under the F + AnE condition (p < 0.05). During AE, there were no differences in IRH, glycemia, or NO between groups, but LPO was significantly higher after F supplementation. These results suggest that the addition of fructose to a single G supplement ingested before a glycolitic exercise can modify the glucoregulation and increases ischemic reactive hyperemia.

Fructose addition to a glucose supplement modifies perceived exertion during strength and endurance exercise.

Da Silva-Grigoletto, ME, Fernández, JM, de Sá, CA, Gómez-Puerto, JR, Vaamonde, D, and Pérez-Jiménez, F. Fructose addition to a glucose supplement modifies perceived exertion during strength and endurance exercise. J Strength Cond Res 24(12): 3334-3342, 2010-The addition of fructose (F) to a glucose (G) supplement may modify the metabolic response during exercise; however, its effect on perceived exertion (PE) and its influence on postprandial metabolism have not been jointly studied in different types of exercise. This study sought to assess the acute effects of F addition to a G supplement on PE and on the postprandial metabolic response during a single bout of either strength exercise (SE) or endurance exercise (EE). Twenty physically trained men ingested an oral dose of G or GF 15 minutes before starting a 30-minute session of SE (10 sets of 10 repetitions of half squat) or EE (cycling). The combination resulted in 4 randomized interventions in a crossover design in which all subjects performed all experimental conditions: G + SE, GF + SE, G + EE, and GF + SE. Perceived exertion, heart rate (HR), G, insulin, lactate, and urinary catecholamine levels were measured before exercise, during the exercise, and during acute recovery. Perceived exertion during exercise was lower for GF than for G during SE and EE (mean ± SD; 8.95 ± 0.62 vs. 9.26 ± 0.65, p < 0.05 and 7.47 ± 0.84 vs. 7.74 ± 0.93, p < 0.05, respectively). The glycemic peak in GF + SE was lower than in G + SE (p < 0.05), and there was a second peak during recovery (p < 0.05), whereas in EE, no difference in blood G levels was noted between G and GF supplements. Moreover, HR, urinary adrenalin, and noradrenalin were lower in GF than in G (p < 0.05), though only for EE. The results showed that PE is positively affected by GF supplementation for both SE and EE and thus may be a useful dietary strategy for helping to achieve higher training loads.

Respostas metabólicas à suplementação com frutose em exercício de força de membros inferiores

Due to its insulin-independent metabolism, fructose promotes significant changes in liver metabolism, promoting a metabolic surrounding favorable to the glucose as well as lipids metabolism during the exercise. This condition has been widely studied in endurance exercises; however, none study about fructose supplementation in strength exercise (SE) was found. This study aimed to assess the acute effects of the fructose addition to a glucose supplement on lipid metabolism in strength exercise. Twenty trained male subjects ingested a glucose (G) or glucose plus fuctose (G+F) supplement, 15 minutes before practicing a strength exercise (10 sets of 10 repetitions). The subjects were tested randomly in a crossover design and with a week of pause in two experimental conditions: SE+(G) and SE+(G+F). The analysis of the results showed that values of triglycerides during the exercise were higher (p 0.05), but they were higher in G+F than in G (p < 0.05) during recovery. Perceived exertion (PE) was lower (p < 0.05) in G+F than in G. It can be concluded that the G+F supplementation positively affects the lipid metabolism during the strength exercise and favors its metabolism immediately after the effort, promoting a metabolic condition that reflects on a condition that favorably affects the PE.