Does Performing Different Resistance Exercises for the Same Muscle Group Induce Non-homogeneous Hypertrophy?

The study aimed to compare the effect of performing the same or different exercises for a muscle group on resistance training (RT) sessions on muscle hypertrophy at different sites along muscle length. Twenty-two detrained men (23.3±4.1 years) were randomly allocated to the following groups: a group that performed the same exercises in all training sessions (N-VAR=11) or one that varied the exercises for the same muscle groups (VAR=11). All were submitted to 3 weekly sessions for nine weeks. Muscle thickness was assessed at the proximal, middle, and distal sites of the lateral and anterior thigh, elbow flexors, and extensors by B-mode ultrasound. The VAR group significantly increased all the sites analyzed (P<0.05). Furthermore, the proximal site of the lateral thigh showed a larger relative increase when compared to the middle site (P<0.05). In contrast, the N-VAR group were not revealed significant improvements only for the middle site of the lateral thigh and the proximal site of the elbow flexors (P>0.05). Our results suggest that to perform different resistance exercises can induce hypertrophy of all sites assessed in detrained young men.

Reliability and Validity of a Novel Wearable Device for Measuring Elbow Strength

Muscle strength is an important clinical outcome in rehabilitation and sport medicine, but options are limited to expensive but accurate isokinetic dynamometry (IKD) or inexpensive but less accurate hand-held dynamometers (HHD). A wearable, self-stabilizing, limb strength measurement device (LSMD) was developed to fill the current gap in portable strength measurement devices. The purpose of this study was to evaluate the reliability and validity of the LSMD in healthy adults. Twenty healthy adults were recruited to attend two strength testing sessions where elbow flexor and extensor strength was measured with the LSMD, with HHD and with IKD in random order, by two raters. Outcomes were intra-rater repeatability, inter-rater reproducibility and inter-session reproducibility using intra-class correlation coefficients (ICC). Limits of agreement and weighted least products regression were used to test the validity of the LSMD relative to the criterion standard (IKD), and calibration formulas derived to improve measurement fidelity. ICC values for the LSMD were >0.90 for all measures of reliability and for both muscle groups, but over-predicted extensor strength and under-predicted flexor strength. Validity was established by transforming the data with the criterion standard-based calibration. These data indicate that the LSMD is reliable and conditionally valid for quantifying strength of elbow flexors and extensors in a healthy adult population.

Indian Subcontinent’s First Bilateral Supracondylar Level Upper Limb Transplantation

Introduction This is the first case of supracondylar level transplant from the Indian subcontinent, performed for a bilateral below elbow amputee. It has a completely different set of challenges for the transplant team, with a relatively shorter ischemia time window.The technical considerations for the same have been discussed in detail in this article. Materials and Methods The patient was a 19-year-old female who lost her both upper limbs at proximal forearm level due to severe crush injury following a road traffic accident. Insufficient bone length on either side necessitated a supracondylar level transplant. The preoperative workup included detailed clinical evaluation, biochemical, and psychological evaluation.The donor was a young brain-dead, male patient from a hospital, 30 minutes away. The donor and recipient preparations in this case were unique. The recipient’s own elbow flexors and extensors were used while the elbow joint was from the donor. The specific challenges we faced during this procedure have been described in detail. Results The transplantation has been a complete technical success, with the patient rehabilitated back to her independent life style. This article describes only the technical considerations. The functional recovery aspect is part of an another soon to be published manuscript. Conclusion Supracondylar level arm-transplant requires a highly coordinated team effort with precise preoperative planning, along with meticulous attention to detail to achieve a successful outcome. In properly selected patients, it could be a life-changing procedure, worth all the effort.

Can the positions of the spastic upper limb in stroke survivors help muscle choice for botulinum toxin injections?

ABSTRACT Motor impairments in stroke survivors are prevalent and contribute to dependence in daily activities, pain and overall disability, which can further upper-limb disability. Treatment with botulinum toxin A (BoNT-A) is indicated for focal spasticity and requires knowledge of biomechanics and anatomy to best select muscles to be injected in the limb. Objective: We aimed to describe the frequency of posture patterns in a Brazilian sample of stroke survivors and correlate them with recommendations of muscle selection for treatment with BoNT-A. Methods: Fifty stroke patients with spastic upper limbs scheduled for neuromuscular block were photographed and physically examined, to be classified by three independent evaluators according to Hefter's classification. Muscles that were injected with BoNT-A by their routine doctors were retrieved from medical charts. Results: Pattern III and IV were the most common (64.7%, 21.6%). We further subclassified pattern III according to the rotation of the shoulder, which effectively interfered in muscle choice. The muscles most frequently treated were shoulder adductors and internal rotators, elbow flexors and extensors, in forearm, the pronator teres and finger and wrist flexors, and, in the hand the adductor pollicis. Conclusion: Frequencies of upper-limb postures differed from previous reports. Other clinical features, besides spasticity, interfered with muscle choice for BoNT-A injection, which only partially followed the recommendations in the literature.

Effects of equal-volume resistance training with different training frequencies in muscle size and strength in trained men

Background The objective of the present study was to compare the effects of equal-volume resistance training (RT) performed with different training frequencies on muscle size and strength in trained young men. Methods Sixteen men with at least one year of RT experience were divided into two groups, G1 and G2, that trained each muscle group once and twice a week, respectively, for 10 weeks. Elbow flexor muscle thickness (MT) was measured using a B-Mode ultrasound and concentric peak torque of elbow extensors and flexors were assessed by an isokinetic dynamometer. Results ANOVA did not reveal group by time interactions for any variable, indicating no difference between groups for the changes in MT or PT of elbow flexors and extensors. Notwithstanding, MT of elbow flexors increased significantly (3.1%, P < 0.05) only in G1. PT of elbow flexors and extensors did not increase significantly for any group. Discussion The present study suggest that there were no differences in the results promoted by equal-volume resistance training performed once or twice a week on upper body muscle strength in trained men. Only the group performing one session per week significantly increased the MT of their elbow flexors. However, with either once or twice a week training, adaptations appear largely minimal in previously trained males.

The effects of adding single-joint exercises to a multi-joint exercise resistance training program on upper body muscle strength and size in trained men

The aim of this study was compare changes in upper body muscle strength and size in trained men performing resistance training (RT) programs involving multi-joint plus single-joint (MJ+SJ) or only multi-joint (MJ) exercises. Twenty young men with at least 2 years of experience in RT were randomized in 2 groups: MJ+SJ (n = 10; age, 27.7 ± 6.6 years) and MJ (n = 10; age, 29.4 ± 4.6 years). Both groups trained for 8 weeks following a linear periodization model. Measures of elbow flexors and extensors 1-repetition maximum (1RM), flexed arm circumference (FAC), and arm muscle circumference (AMC) were taken pre- and post-training period. Both groups significantly increased 1RM for elbow flexion (4.99% and 6.42% for MJ and MJ+SJ, respectively), extension (10.60% vs 9.79%, for MJ and MJ+SJ, respectively), FAC (1.72% vs 1.45%, for MJ and MJ+SJ, respectively), and AMC (1.33% vs 3.17% for MJ and MJ+SJ, respectively). Comparison between groups revealed no significant difference in any variable. In conclusion, 8 weeks of RT involving MJ or MJ+SJ resulted in similar alterations in muscle strength and size in trained participants. Therefore, the addition of SJ exercises to a RT program involving MJ exercises does not seem to promote additional benefits to trained men, suggesting MJ-only RT to be a time-efficient approach.

A DESCRIPTIVE PROFILE OF ISOMETRIC MUSCLE STRENGTH AND MUSCLE STRENGTH IMBALANCE IN YOUNG TENNIS PLAYERS

Background. Tennis is assumed as asymmetric sport, prolonged training practice could affect muscle strength imbalance. Muscle strength functional ratio imbalance could be a reason for poor posture, physical weakness and increased risk of injury. The purpose of the research was to evaluate young tennis players’ main muscle group strength topography and to investigate the level of different muscles groups’ bi-lateral and contra-lateral imbalance. Methods. The participants of the study were six young right handed competitive tennis players (girls, age 11.4 ± 0.5 years, tennis experience 4.7 ± 0.6 years). Examination of main muscles groups was performed with an isokinetic dynamometer. Results. Young tennis players have pronounced bi-lateral imbalance between shoulder joint extensors and flexors (25%), internal and external rotators (36%), left elbow flexors and extensors (58%), wrist pronator and supinator (the right hand 17%, left 48%), hip flexors and extensors (35%); knee joint flexors and extensors (60%); ankle dorsal flexors and plantar flexors (59%); spine and abdominal muscles (48%). It was detected that young tennis players have pronounced contra-lateral imbalance between right and left internal rotators of the shoulder joint (27%) and external rotators (26%), wrist joint supinators (41%). Conclusions. To avoid the increase in muscle bi-lateral imbalance it is highly recommended to pay more attention to shoulder adductors and shoulder external rotators, elbow flexors and extensors, wrist supinators and extensors, knee extensors, ankle plantar flexors and spine flexors. For contra-lateral imbalance prevention in addition to train non-dominant upper extremity muscles: shoulder internal and external rotators, wrist supinators.