RESUMO
Manufacturers of Perfect·Pushup™ handgrips claim enhanced muscular recruitment when compared with the conventional hand-on-floor push-up exercise. Electromyographic (EMG) data were recorded using surface electrodes from the right-sided triceps brachii, pectoralis major, serratus anterior (SA), and posterior deltoid muscles during push-ups performed from 3 different hand positions: (a) shoulder width, (b) wide base, and (c) narrow base (NB). Push-ups were performed under 2 conditions: (a) standard push-up and (b) Perfect·Pushup™ handgrips. We recruited 20 healthy subjects, 11 men (24.9 ± 2.6 years) and 9 women (23.8 ± 1 years). Subjects completed 3 consecutive push-ups for each hand position under both conditions. Push-up speed was controlled using a metronome, and testing order was randomized. We recorded peak EMG activity for each muscle during each of the push-ups and normalized EMG values by maximum muscle contractions (% maximum voluntary isometric contraction [MVIC]). Electromyographic data were analyzed with 3 (hand position) × 2 (condition) repeated-measures analysis of variance with a post hoc Bonferroni-adjusted simple effects test to detect significant position effects for position by condition interactions (α = 0.05). A push-up required considerable muscle activation of the triceps brachii (73-109% MVIC), pectoralis major (95-105% MVIC), SA (67-87% MVIC), and posterior deltoid (11-21% MVIC) whether performed using the conventional hand-on-floor position or the Perfect·Pushup™ handgrips. The NB hand position was most effective for preferentially activating the triceps brachii and posterior deltoid muscles. Based upon EMG activation from 4 muscles, the Perfect·Pushup™ handgrips do not appear to preferentially enhance muscular recruitment when compared with the conventional push-up method.
Assuntos
Exercício Físico/fisiologia , Mãos/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Análise de Variância , Braço/fisiologia , Eletromiografia , Feminino , Humanos , Contração Isométrica , Masculino , Ombro/fisiologia , Tórax/fisiologia , Adulto JovemRESUMO
An audience response system (ARS) has become popular among educators in medicine and the health professions because of the system's ability to engage listeners during a lecture presentation. No one has described the usefulness of ARS technology during planned nonlecture peer teaching sessions in gross anatomy instruction for health professionals. The unique feature of each peer teaching session was a nongraded 12-15 item ARS quiz assembled by six second-year doctor of physical therapy (DPT) students and purposely placed at the beginning of the review session for those first-year DPT students in attendance. This study used a ten-item questionnaire and a five-point Likert scale in addition to three open ended questions to survey perceptions of both first-year and second-year DPT students about the usefulness of ARS technology implemented during weekly interactive peer teaching sessions during a semester course in Anatomy for Physical Therapists. First-year students overwhelmingly acknowledged the ARS system permitted each student to self-assess his/her preparedness for a quiz or examination and compare his/her performance with that of classmates. Peer teachers recognized an ARS quiz provided them an opportunity to: (1) estimate first-year students' level of understanding of anatomical concepts; and (2) effectively prepare first-year students for their weekly quizzes and future examinations. On the basis of the mutual benefits derived by both students/tutees and teachers/tutors, physical therapist educators may wish to consider using ARS technology to enhance teaching methods for a class in gross human anatomy.