Search results for "electromyography"
showing 10 items of 672 documents
Feasibility, safety and muscle activity during flywheel vs traditional strength training in adult patients with severe haemophilia
2021
INTRODUCTION: Eccentric training has been associated with several specific physiological adaptations. The flywheel machine is one of the easiest ways of performing eccentric overload training. However, no studies evaluated its feasibility, safety and muscle activity in patients with haemophilia (PWH).AIM: To evaluate feasibility and safety and compare muscle activity during flywheel vs weight machine knee extension exercise in severe PWH.METHODS: Eleven severe PWH [mean age of 33.5 (8.1) years] participated in this cross-sectional study after receiving prophylactic treatment. Surface electromyography (EMG) signals were recorded for the rectus femoris during the knee extension exercise perfo…
Acute and prolonged reduction in joint stiffness in humans after exhausting stretch-shortening cycle exercise.
2002
The purpose of the present study was to examine the acute and long-term fatigue effects of exhausting stretch-shortening cycle (SSC) exercise on the stiffness of ankle and knee joints. Five subjects were fatigued on a sledge apparatus by 100 maximal rebound jumps followed by continuous submaximal jumping until complete exhaustion. Neuromuscular fatigue ef- fects were examined in submaximal hopping (HOP) and in maximal drop jumps (DJ) from 35 (DJ35) and 55 cm (DJ55) heights on a force plate. Additional force and reflex measurements were made using an ankle ergom- eter. Jumping tests and ankle ergometer tests were car- ried out before, immediately after, 2 h (2H), 2 days and 7 days (7D) after…
Neuromuscular adaptations and serum hormones in women during short-term intensive strength training
1992
The effects were investigated in ten women of intensive heavy resistance strength training lasting for 3 weeks on electromyographic (EMG) activity, muscle cross-sectional area (CSA) and voluntary force production characteristics of leg extensor muscles. Blood samples for the determinations of serum hormones were taken from five of the subjects. Significant increases occurred in the higher force portions of the isometric force-time curve with an increase of 9.7 (SD 8.4)% (P less than 0.01) in maximal peak force. An increase of 15.8 (SD 20.9)% (P less than 0.05) took place also in the maximal neural activation (integrated EMG) of the trained muscles, while an enlargement of 4.6 (SD 7.4)% (P l…
Effects of intra-session exercise sequence during water-based concurrent training.
2013
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 brac…
Changes in a patient with neck pain after application of ischemic compression as a trigger point therapy
2010
Objective To describe the immediate effects of ischemic compression (IC) as a trigger point therapy in a case of a patient with neck pain. The application of IC is a safe and effective method to successfully treat elicited myofascial trigger points. The purpose of this method is to deliberate the blockage of blood in a trigger point area in order to increase local blood flow. This washes away waste products, supplies necessary oxygen and helps the affected tissue to heal. In this case study, we treated a 27-year-old female patient with a medical report of neck pain for at least four months. The physical examination revealed a neck pain and stiffness at the left side and pain increases when …
Neuromuscular and hormonal responses in elite athletes to two successive strength training sessions in one day
1988
Acute neuromuscular and endocrine adaptations to weight-lifting were investigated during two successive high intensity training sessions in the same day. Both the morning (I) (from 9.00 to 11.00 hours) and the afternoon (II) (from 15.00 hours to 17.00 hours) training sessions resulted in decreases in maximal isometric strength (p less than 0.01 and less than 0.05), shifts (worsening) in the force-time curve in the absolute scale (p less than 0.05 and ns.) and in decreases in the maximal integrated EMG (p less than 0.01 and less than 0.05) of the selected leg extensor muscles. Increases in serum total (p less than 0.05) and free testosterone (p less than 0.01) and in cortisol (p less than 0.…
EMG, muscle fibre and force production characteristics during a 1 year training period in elite weight-lifters.
1987
The effects of a 1 year training period on 13 elite weight-lifters were investigated by periodical tests of electromyographic, muscle fibre and force production characteristics. A statistically non-significant increase of 3.5% in maximal isometric strength of the leg extensors, from 4841 +/- 1104 to 5010 +/- 1012 N, occurred over the year. Individual changes in the high force portions of the force-velocity curve correlated (p less than 0.05-0.01) with changes in weight-lifting performance. Training months 5-8 were characterized by the lowest average training intensity (77.1 +/- 2.0%), and this resulted in a significant (p less than 0.05) decrease in maximal neural activation (IEMG) of the m…
Mechanical efficiency in athletes during running.
2007
The purpose of this study was to compare the external mechanical efficiency (ME) between power-trained athletes (n = 5) and endurance-trained athletes (n = 5). The relationships between biomechanical variables and metabolic cost were also investigated. The subjects ran at 3 different speeds (2.50 m.s-1, 3.25 m.s-1 and 4.00 m.s-1) both on the treadmill and on the track. The external work of the subjects was determined by a kinematic arm, and energy expenditure was determined by measuring oxygen consumption and respiratory exchange ratio. Biomechanical parameters included ground reaction forces, angular displacements of the knee and ankle joints and electromyography (EMG) of the selected musc…
Deadlift muscle force and activation under stable and unstable conditions.
2010
The objective of this study was to compare the production of force and paraspinal muscle activity between deadlifts carried out in a standard way and with different instability devices (Bosu and T-Bow). Deadlifts involve the performance of muscle activities with dynamic and isometric characteristics. Thirty-one subjects participated voluntarily in the study. Initially, they performed an isometric test for 5 seconds in each condition. After that, they performed a set of 5 repetitions with 70% of the maximum isometric force obtained in each one of the previously evaluated conditions. During the isometric tests, records of electromyographic activity and force production were obtained, whereas …
Long-term use of high-heeled shoes alters the neuromechanics of human walking
2012
Human movement requires an ongoing, finely tuned interaction between muscular and tendinous tissues, so changes in the properties of either tissue could have important functional consequences. One condition that alters the functional demands placed on lower limb muscle-tendon units is the use of high-heeled shoes (HH), which force the foot into a plantarflexed position. Long-term HH use has been found to shorten medial gastrocnemius muscle fascicles and increase Achilles tendon stiffness, but the consequences of these changes for locomotor muscle-tendon function are unknown. This study examined the effects of habitual HH use on the neuromechanical behavior of triceps surae muscles during w…