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Purpose: The purpose of this study was to investigate electromyographic amplitude (EMG AMP), EMG mean power frequency (MPF), exercise volume (VOL), total work and muscle activation (iEMG), and time under concentric load (TUCL) during, and muscle cross-sectional area (mCSA) before and after 3 sets to failure at 80 vs. 30 % 1RM resistance exercise.Methods: Nine men (mean ± SD, age 21.0 ± 2.4 years, resistance training week(-1) 6.0 ± 3.7 h) and 9 women (age 22.8 ± 3.8 years, resistance training week(-1) 3.4 ± 3.5 h) completed 1RM testing, followed by 2 experimental sessions during which they completed 3 sets to failure of leg extension exercise at 80 or 30 % 1RM. EMG signals were collected to quantify EMG AMP and MPF during the initial, middle, and last repetition of each set. Ultrasound was used to assess mCSA pre- and post-exercise, and VOL, total work, iEMG, and TUCL were calculated.Results: EMG AMP remained greater at 80 % than 30 % 1RM across all reps and sets, despite increasing 74 and 147 % across reps at 80 and 30 % 1RM, respectively. EMG MPF decreased across reps at 80 and 30 % 1RM, but decreased more and was lower for the last reps at 30 than 80 % 1RM (71.6 vs. 78.1 % MVIC). mCSA increased more from pre- to post-exercise for 30 % (20.2-24.1 cm(2)) than 80 % 1RM (20.3-22.8 cm(2)). VOL, total work, iEMG and TUCL were greater for 30 % than 80 % 1RM.Conclusion: Muscle activation was greater at 80 % 1RM. However, differences in volume, metabolic byproduct accumulation, and muscle swelling may help explain the unexpected adaptations in hypertrophy vs. strength observed in previous studies. [ABSTRACT FROM AUTHOR]

Purpose: This study examined: (1) the sustainability of the critical heart rate (CHR) minus 5 b min(-1) (CHR - 5) and CHR plus 5 b min(-1) (CHR + 5); (2) the ratings of perceived exertion (RPE), velocity, [Formula: see text], minute ventilation ([Formula: see text]), breathing frequency (f b ), and electromyographic amplitude (EMG AMP) and EMG mean power frequency (MPF) responses during treadmill running at CHR - 5 and CHR + 5 to determine what factors underlie the perception of effort when heart rate (HR) is held constant; and (3) the relationships among RPE, [Formula: see text], and HR, to determine which variable(s) reflect exhaustion during exercise performed at a constant HR.Methods: The CHR was determined in eight runners (mean ± SD; age = 24 ± 3 years) from a series of four exhaustive, constant velocity runs. The RPE, velocity, [Formula: see text], [Formula: see text], f b , EMG AMP, and EMG MPF responses were recorded during runs at the CHR - 5 and CHR + 5.Results: At CHR - 5, RPE, f b, and EMG MPF increased, while velocity, [Formula: see text], [Formula: see text], and EMG AMP decreased. At CHR + 5, RPE and f b increased, velocity, [Formula: see text], [Formula: see text], and EMG AMP decreased, and EMG MPF remained constant.Conclusions: The close association between f b and RPE throughout the run at CHR - 5 and during the last 50 % of the run at CHR + 5 indicated that muscle afferents may have provided feedback from metabolic and mechanical stimuli that contributed to the perceptual responses. In addition, only RPE consistently indicated exhaustion and the current findings supported its use to monitor exercise performed at a constant HR. [ABSTRACT FROM AUTHOR]

Objectives In light of current FDA guidelines on opioid use in children, we sought to determine the risk of post-tonsillectomy hemorrhage (PTH) in children who received ibuprofen with acetaminophen versus those who received narcotic with acetaminophen for postoperative pain control. Methods This was an IRB-approved retrospective chart review of patients at a tertiary-care pediatric center. The medical records of 449 children who received acetaminophen and ibuprofen following intracapsular tonsillectomy with or without adenoidectomy were reviewed (NSAID group) and compared with medical records of 1731 children who underwent intracapsular tonsillectomy and received acetaminophen with codeine or hydrocodone with acetaminophen postoperatively (narcotic group). Main outcome measure was the incidence of PTH requiring return to the operating room. Secondary outcome measures included incidence of primary PTH, secondary PTH, and postoperative evaluation in the emergency department or readmission for pain and/or dehydration. Results Incidence of PTH requiring return to the operating room was higher in the NSAID group (1.6%) compared with the narcotic group (0.5%), P = 0.01. Incidence of primary PTH was significantly higher in the NSAID group (2%) versus the narcotic group (0.12%), P < 0.0001. Incidence of secondary PTH was 3.8% in the NSAID group and 1.1% in the narcotic group ( P < 0.0001). Conclusion Use of ibuprofen after intracapsular tonsillectomy in children is associated with statistically significant increase in PTH requiring return to the operating room, as well as an increase in overall rates of both primary and secondary PTH. Ibuprofen provides pain control that is at least equivalent to narcotic and is not associated with respiratory depression. Further study of ibuprofen use in the post-tonsillectomy patient is warranted. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: We compared absolute and normalized values for peak torque (PT), mean power (MP), rate of velocity development, and electromyography (EMG) amplitude during maximal isometric and concentric isokinetic leg extension muscle actions, as well as the %decrease in PT and %increase in MP from 1.05 to 3.14 rad·s−1 in younger versus older men. Methods: Measurements were performed twice for reliability. Isokinetic measurements were normalized to the isometric muscle actions. Results: Absolute isometric PT, isokinetic PT and MP, and EMG amplitudes at 1.05 and 3.14 rad·s−1 were greater in the younger men, although normalizing to isometric PT eliminated the age differences. The older men exhibited greater %decrease in PT (37.2% vs. 31.3%) and lower %increase in MP (87.6% vs. 126.4%) regardless of normalization. Conclusions: Normalization eliminated absolute differences in isokinetic strength and power, but the relative differences from slow to fast velocities may reflect dynapenia characterized by age-related decreases in fast-twitch fiber function. Muscle Nerve 52: 120-130, 2015 [ABSTRACT FROM AUTHOR]

This review focuses on contact dermatitis as an adverse effect of a selection of topically used herbal medicinal products for which the European Medicines Agency has completed an evaluation up to the end of November 2013 and for which a Community herbal monograph has been produced. Part 2: Echinacea purpurea Moench- Lavandula angustifolia Mill. [ABSTRACT FROM AUTHOR]

Thirteen subjects (mean ± SD age: 21.8 ± 2.6 yrs) performed an incremental cycling test and 4, 8-min submaximal rides (65 to 80% of VO2 peak) to: (a) compare power outputs and relative intensities that corresponded to the gas exchange threshold (GET), ventilatory threshold (VT), respiratory compensation point (RCP), physical working capacity (PWC) at oxygen consumption PWCVO2, heart rate (PWCHRT), and rating of perceived exertion (PWCOMNI) thresholds; and (b) examine the relationships among the fatigue thresholds and the exercise intensity domains. The RCP (184 ± 47 W) was significantly (P≤0.0033) greater than the GET (142 ± 38 W), VT (143 ± 40 W), PWCVO2 (106 ± 34 W), PWCHRT (108 ± 34 W), and PWCOMNI (112 ± 34 W). The GET and VT were significantly greater than the PWCVO2, PWCHRT, and PWCOMNI, but there were no differences among the PWCVO2, PWCHRT, and PWCOMNI. These findings suggest that the PWCVO2, PWCHRT, and PWCOMN fell within the moderate intensity domain, and share a common physiological mechanism that was different from those associated with the GET, VT, and RCP. [ABSTRACT FROM AUTHOR]

This review focuses on contact dermatitis as an adverse effect of a selection of topically used herbal medicinal products for which the European Medicines Agency has completed an evaluation up to the end of November 2013 and for which a Community herbal monograph has been produced. Part 1: Achillea millefolium L.- Curcuma longa L. [ABSTRACT FROM AUTHOR]

This study examined the age-related growth patterns for body build and anthropometric characteristics of wrestlers between 7 and 18 yrs of age. Three hundred and thirty-one male wrestlers (age = 13.5 ± 3.2 yrs; height (HT) = 157.2 ± 17.3 cm; and body mass (BM) = 51.2 ± 16.3 kg) participated in this study. The relationships for age versus body build (somatotype ratings) and anthropometric characteristics (HT, BM, diameters, circumferences, and ratios) were analyzed. Across age, the wrestlers exhibited increases in HT, BM, and body mass index (BMI), maintained a mesomorphic body build, and demonstrated greater rates of increases in upper than lower body anthropometric ratios associated with frame size and fat-free mass. Thus, the findings indicate that the young wrestlers had a unique physique characterized by pronounced muscularity, a triangular upper body frame, and greater rates of development in the upper body segments than in the lower body segments. [ABSTRACT FROM AUTHOR]

Introduction We compared peak and submaximal mean values for neuromuscular and metabolic parameters between ramp (15 W·min−1) and step (30 W increments every 2 min) incremental cycle ergometer tests. Methods Thirteen healthy adults (7 men and 6 women; mean ± SD age = 23.4 ± 3.3 years) performed randomly ordered ramp or step incremental tests. Two-way repeated measures analyses of variance were used to analyze the data. Results The ramp incremental test resulted in lower mean EMG amplitude, O2, and HR values at the common power outputs, with no differences for MMG amplitude values. Conclusions It is possible that the cumulative effect of producing an increased amount of work during the step (total work = 75.83 kJ) vs. ramp (total work = 65.60 kJ) incremental cycle ergometer tests at the common power outputs may have contributed to the greater fatigue-induced increase in muscle recruitment and/or firing rate, oxygen consumption, and heart rate. Muscle Nerve, 2013 [ABSTRACT FROM AUTHOR]