PAULO HENRIQUE MARCHETTI
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- Muscle strength, postural balance, and cognition are associated with braking time during driving in older adults(2016) ALONSO, Angelica C.; PETERSON, Mark D.; BUSSE, Alexandre L.; JACOB-FILHO, Wilson; BORGES, Mauricio T. A.; SERRA, Marcos M.; LUNA, Natalia M. S.; MARCHETTI, Paulo H.; GREVE, Julia M. D. A.Background: Despite the well-known declines in driving performance with advancing age, there is little understanding of the specific factors that predict changes in key determinants such as braking time. Objectives: The aims of this study were to determine the extent to which age, muscle strength, cognition and postural balance are associated with braking performance in middle-aged and older adults. Methods: Male and female middle-aged adults (n = 62, age = 39.3 +/- 7.1 years) and older adults (n = 102, age = 70.4 +/- 5.8 years) were evaluated for braking performance, as well as in several motor and cognitive performance tasks. The motor evaluation included isokinetic ankle plantar flexor muscle strength, handgrip strength, and postural balance with and without a cognitive task. The cognitive assessment included the Mini Mental State Examination. Braking performance was measured using a driving simulator. Results: Older adults exhibited 17% slower braking time, lower strength, and poorer performance in the postural balance (p < 0.001). For both older and middle-aged adults, significant correlates of braking time included performance in the postural balance tests, muscle strength, and cognitive function. However, after full model adjustment, only postural balance and cognitive function were significantly associated. Conclusion: Muscle strength, postural balance, and cognition are associated with braking time, and may affect the safety of and driving performance in older adults. These findings may help to inform specific targeted interventions that could preserve driving performance during aging.
article 22 Citação(ões) na Scopus Comparison between Pre-Exhaustion and Traditional Exercise Order on Muscle Activation and Performance in Trained Men(2016) SOARES, Enrico Gori; BROWN, Lee E.; GOMES, Willy Andrade; CORREA, Daniel Alves; SERPA, Erica Paes; SILVA, Josinaldo Jarbas da; VILELA JUNIOR, Guanis de Barros; FIORAVANTI, Gustavo Zorzi; AOKI, Marcelo Saldanha; LOPES, Charles Ricardo; MARCHETTI, Paulo HenriqueThe purpose of this study was to measure the acute effects of pre-exhaustion vs. traditional exercise order on neuromuscular performance and sEMG in trained men. Fourteen young, healthy, resistance trained men (age: 25.5 +/- 4.0 years, height: 174.9 +/- 4.1 cm, and total body mass: 80.0 +/- 11.1 kg) took part of this study. All tests were randomized and counterbalanced for all subjects and experimental conditions. Volunteers attended one session in the laboratory. First, they performed ten repetition maximum (10RM) tests for each exercise (bench press and triceps pushdown) separately. Secondly, they performed all three conditions at 10RM: pre-test (bench press and triceps pushdown, separately), pre-exhaustion (triceps push-down+ bench press, PE) and traditional (bench press+triceps pushdown, TR), and rested 30 minutes between conditions. Results showed that pre-test was significantly greater than PE (p = 0.031) but not different than TR, for total volume load lifted. There was a significant difference between the pre-test and the time-course of lactate measures (p = 0.07). For bench press muscle activity of the pectoralis major, the last repetition was significantly greater than the first repetition (pre-test: p = 0.006, PE: p = 0.016, and TR: p = 0.005). Also, for muscle activity of the triceps brachii, the last repetition was significantly greater than the first repetition (pre-test: p = 0.001, PE: p = 0.005, and TR: p = 0.006). For triceps pushdown, muscle activity of the triceps brachii, the last repetition was significantly greater than the first repetition (pre-test: p = 0.006, PE: p = 0.016, and TR: p = 0.005). For RPE, there were no significant differences between PE and TR (p = 0.15). Our results suggest that exercise order decreases repetitions performed, however, neuromuscular fatigue, lactate, and RPE are not impacted. The lack of difference in total volume load lifted between PE and TR might explain, at least in part, the similar metabolic and perceptual responses.- MUSCLE ACTIVATION DIFFERS BETWEEN PARTIAL AND FULL BACK SQUAT EXERCISE WITH EXTERNAL LOAD EQUATED(2017) SILVA, Josinaldo J. da; SCHOENFELD, Brad J.; MARCHETTI, Priscyla N.; PECORARO, Silvio L.; GREVE, Julia M. D.; MARCHETTI, Paulo H.Changes in range of motion affect the magnitude of the load during the squat exercise and, consequently, may influence muscle activation. The purpose of this study was to evaluate muscle activation between the partial and full back squat exercise with external load equated on a relative basis between conditions. Fifteen young, healthy, resistance-trained men (age: 26 +/- 5 years, height: 173 +/- 6 cm) performed a back squat at their 10 repetition maximum (10RM) using 2 different ranges of motion (partial and full) in a randomized, counterbalanced fashion. Surface electromyography was used to measure muscle activation of the vastus lateralis, vastus medialis, rectus femoris, biceps femoris (BF), semitendinosus, erector spinae, soleus (SL), and gluteus maximus (GM). In general, muscle activity was highest during the partial back squat for GM (p = 0.004), BF (p = 0.009), and SL (p = 0.031) when compared with full-back squat. There was no significant difference for rating of perceived exertion between partial and full back squat exercise at 10RM (8 +/- 1 and 9 +/- 1, respectively). In conclusion, the range of motion in the back squat alters muscle activation of the prime mover (GM) and stabilizers (SL and BF) when performed with the load equated on a relative basis. Thus, the partial back squat maximizes the level of muscle activation of the GM and associated stabilizer muscles.
- Muscle Activation Pattern During Isometric Ab Wheel Rollout Exercise in Different Shoulder Angle-Positions(2015) MARCHETTI, Paulo Henrique; SCHOENFELD, Brad J.; SILVA, Josinaldo Jarbas da; GUISELINI, Mauro Antonio; FREITAS, Fabio Sisconeto de; PECORARO, Silvio Luiz; GOMES, Willy Andrade; LOPES, Charles RicardoOBJECTIVE: To investigate muscle activation of the shoulder extensors and trunk stabilizers by surface electromyography (sEMG) activity during the isometric Ab Wheel Rollout exercise in different shoulder joint positions. METHOD: We recruited 8 young, healthy, resistance trained men (age: 25 ± 3 years, height: 178 ± 5 cm, and total body mass: 81 ± 2 kg). All subjects performed two sets of 10 sec. maximal isometric contractions of the Ab Wheel Rollout exercise keeping the knees fixed on the floor and the arms taut. To perform the exercise, all subjects were randomly assessed in the following three positions related to the angle between the arms and trunk, in random order: arms aligned vertically with the Ab Wheel Rollout exercise (neutral); 90º and 150º. A rest period of 5 minutes was provided between tests. The sEMG signals were recorded in the following muscles: Latissimus Dorsi; Pectoralis Major; Erector Spinae; Rectus Abdominis. RESULTS: There were significant increases in Rectus Abdominis muscle activity between: neutral vs. 90º, neutral vs. 150º and 90º vs. 150º. There was a significant increase in Pectoralis Major muscle activity between neutral x 150º. CONCLUSION: The present findings indicate that (a) Ab Wheel Rollout exercise emphasizes the muscle action of the Pectoralis Major and Rectus Abdominis more than the Latissimus Dorsi and Erector Spinae; (b) the level of muscle activation depends on the external force created by the body mass and lever arm from the center of mass.