scholarly journals Kinetic Analysis of Water Fitness Exercises: Contributions for Strength Development

2019 ◽  
Vol 16 (19) ◽  
pp. 3784 ◽  
Author(s):  
Santos ◽  
Rama ◽  
Marinho ◽  
Barbosa ◽  
Costa
Keyword(s):  
Upper Limb ◽  
Force Production ◽  
Peak Force ◽  
Strength Development ◽  
Isokinetic Dynamometer ◽  
Symmetric Motion ◽  
Pressure System ◽  
Dry Land ◽  
Force Variation ◽  
Selection Of

The evaluation of propulsive forces in water allows the selection of the most appropriate strategies to develop strength during water fitness sessions. The aim of this study was threefold: (i) to analyze the rate of force production; (ii) to analyze the rate of force variation; and (iii) to compare limbs’ symmetry in two water fitness exercises. Twenty-two young health subjects (age: 21.23 ± 1.51 years old, body mass: 67.04 ± 9.31 kg, and height: 166.36 ± 8.01 cm) performed incremental protocols of horizontal adduction (HA) and rocking horse (RHadd), from 105 until 150 b·min–1. Data acquisition required an isokinetic dynamometer and a differential pressure system that allowed the assessment of (a) isometric peak force of dominant upper limb (IsometricFD); (b) propulsive peak force of dominant upper limb (PropulsiveFD); and (c) propulsive peak force of nondominant upper limb (PropulsiveFND). Significant differences were found in the rate of force production (RateFD) between the majority cadences in both exercises. The RateFD reached ~68% of the force in dry-land conditions, and lower cadences promoted a higher rate of force variation (ΔForce). Most actions were asymmetric, except for the HA at 135 b·min–1. In conclusion, the musical cadence of 135 b·min–1 seems to elicit a desired rate of force production with a symmetric motion in both exercises.

scholarly journals Evaluation of Optimal Vibrotactile Feedback for Force-Controlled Upper Limb Myoelectric Prostheses

Sensors ◽  
2019 ◽  
Vol 19 (23) ◽  
pp. 5209 ◽  
Author(s):  
Andrea Gonzalez-Rodriguez ◽  
Jose L. Ramon ◽  
Vicente Morell ◽  
Gabriel J. Garcia ◽  
Jorge Pomares ◽  
...  
Keyword(s):  
Real Time ◽  
Upper Limb ◽  
Closed Loop ◽  
Fine Tuning ◽  
Vibrotactile Feedback ◽  
Loop Control ◽  
Myoelectric Prostheses ◽  
Amplitude Level ◽  
Real Time Application ◽  
Selection Of

The main goal of this study is to evaluate how to optimally select the best vibrotactile pattern to be used in a closed loop control of upper limb myoelectric prostheses as a feedback of the exerted force. To that end, we assessed both the selection of actuation patterns and the effects of the selection of frequency and amplitude parameters to discriminate between different feedback levels. A single vibrotactile actuator has been used to deliver the vibrations to subjects participating in the experiments. The results show no difference between pattern shapes in terms of feedback perception. Similarly, changes in amplitude level do not reflect significant improvement compared to changes in frequency. However, decreasing the number of feedback levels increases the accuracy of feedback perception and subject-specific variations are high for particular participants, showing that a fine-tuning of the parameters is necessary in a real-time application to upper limb prosthetics. In future works, the effects of training, location, and number of actuators will be assessed. This optimized selection will be tested in a real-time proportional myocontrol of a prosthetic hand.

scholarly journals Application of the damage control principles and the use of a local negative pressure system for the prevention of infectious complications in a patient with traumatic separation of the upper limb and massive damage to soft tissues

2020 ◽  
Vol 6 (4) ◽  
pp. 22-25
Author(s):  
I. M. Batyrshin ◽  
M. I. Kizyavka ◽  
D. S. Sklizkov ◽  
Yu. S. Ostroumova ◽  
E. P. Mikhelson ◽  
...  
Keyword(s):  
Upper Limb ◽  
Successful Treatment ◽  
Negative Pressure ◽  
Clinical Case ◽  
Soft Tissues ◽  
Damage Control ◽  
Infectious Complications ◽  
Pressure System

The article presents a clinical case of the successful treatment of a patient with traumatic separation of the upper limb and massive damage to the soft tissues of the upper shoulder and chest. The effectiveness of applying the damage control principles and the method of local negative pressure for the prevention of local and systemic infectious complications is emphasized.

Acute beetroot juice administration improves peak isometric force production in adolescent males

2018 ◽  
Vol 43 (8) ◽  
pp. 816-821 ◽  
Author(s):  
David Bender ◽  
Jeremy R. Townsend ◽  
William C. Vantrease ◽  
Autumn C. Marshall ◽  
Ruth N. Henry ◽  
...  
Keyword(s):  
Isometric Force ◽  
Force Production ◽  
Sprint Performance ◽  
Peak Force ◽  
Adolescent Males ◽  
Height Velocity ◽  
Beetroot Juice ◽  
Repeated Sprint ◽  
Group Time ◽  
Isometric Force Production

The purpose of this study was to examine the effects of acute beetroot juice (BR) administration on repeated sprint performance and isometric force production in adolescent males. Twelve male adolescents (age, 16.8 ± 1.0 years; height, 178.8 ± 9.2 cm; mass, 74.8 ± 12.5 kg; peak height velocity, 2.53 ± 1.2 years) participated in this double-blind, placebo-controlled, crossover designed study. Participants consumed 2 × 70 mL of BR (∼12.9 mmol NO3−; Beet It Sport) or a nitrate-depleted placebo (PL) at 2.5 h prior to performing isometric mid-thigh pulls (IMTP) and 4 repeated 20-s Wingate sprints interspersed with 4 min of rest. Sprint data were analyzed by a 2 × 4 (group × time) repeated-measures ANOVA while a dependent t test was used to compare conditions for IMTP peak force. A significant main effect for time (p < 0.05) was observed for peak power (PP), average power (Pavg), and fatigue index (FI) across sprints. Compared with sprint 1, sprint 4 resulted in significant decreases in PP (p < 0.000; −16.6%) and Pavg (p = 0.000; −21.8%) and FI was significantly elevated (p < 0.000; 15.2%). No significant group × time interactions were observed between conditions for PP (p = 0.402), Pavg (p = 0.479), or FI (p = 0.37). IMTP peak force was significantly higher (p = 0.004; 13.9%) following BR consumption compared with PL. The repeated sprint protocol resulted in significant fatigue while BR did not influence sprint performance. However, it appears BR administration may improve peak force production in adolescent males.

MATLAB-Based Kinematic Analysis on Mechanisms of Multifunctional Wheelchair

2010 ◽  
Vol 97-101 ◽  
pp. 2785-2791
Author(s):  
Ai Ping Li ◽  
Jun Hu ◽  
Jian Guo Zhang
Keyword(s):  
Simulation Model ◽  
Dynamic Simulation ◽  
Upper Limb ◽  
Kinematic Analysis ◽  
Working Condition ◽  
Simulation Tool ◽  
Type Selection ◽  
Motion Parameters ◽  
Selection Of

This paper simplifies the upper limb lifting mechanism of the multifunctional wheelchair, takes the dynamic simulation tool Simulink of MATLAB as a platform, establishes a simulation model for kinematic analysis on the upper limb lifting mechanism, and executes the simulation after all parameters are set. The result shows that such simulation can help to conveniently and accurately get the motion parameters of the mechanism and optimize the parameters immediately, so that reference can be provided for type selection of this mechanism, it can be better understand the working condition of the multifunctional wheelchair, and complete the structure of product prototypes.

Reliability of the Dynamic Strength Index in College Athletes

2015 ◽  
Vol 10 (5) ◽  
pp. 542-545 ◽  
Author(s):  
Christopher Thomas ◽  
Paul A. Jones ◽  
Paul Comfort
Keyword(s):  
College Athletes ◽  
Intraclass Correlation ◽  
Force Production ◽  
Dynamic Strength ◽  
Peak Force ◽  
Dynamic Force ◽  
Strength Index ◽  
Training Interventions ◽  
Change In The Mean ◽  
Change In Mean

Purpose:To determine the reliability of the Dynamic Strength Index (DSI) in college athletes.Method:Nineteen male college athletes performed the squat jump (SJ) and isometric midthigh pull (IMTP) to determine peak force, on 2 separate days. Reliability was assessed by intraclass correlation coefficient (ICC), typical error (TE), percentage change in the mean, smallest worthwhile change (SWC), and coefficient of variation (%CV).Results:Peak force for the SJ was 2137 ± 499 N and 2781 ± 435 N for the IMTP, resulting in a mean DSI of 0.78 ± 0.19. Peak forces in the SJ (ICC = .99, TE = 57.22 N, change in mean = 0.2%, SWC = 4.7%, CV = 2.6%) and IMTP (ICC = .95, TE = 104.22 N, change in mean = 0.5%, SWC = 3.1%, CV = 3.8%) were considered highly reliable between sessions. However, IMTP peak force was the only variable with an overall TE < SWC. The DSI was also highly reliable (ICC = .97, TE = 0.03, change in mean = −0.3%, SWC = 5.1%, CV = 4.6%) between sessions.Conclusion:This study demonstrates that peak force in the SJ and IMTP are reliable, resulting in a reliable assessment of dynamic-force-production capabilities via the DSI. The DSI may be used to guide individualized training interventions and monitor specific adaptations to training. Changes in SJ peak force, IMTP peak force, and DSI were >4.67%, 3.13%, and 5.13%, respectively, identifying meaningful changes in response to training or competition.

The Use of Maximum Strength Measures as a Predictor of Rapid Force Production and Strength Endurance

2017 ◽  
Vol 22 (2) ◽  
pp. 48-59
Author(s):  
Roger O. Kollock ◽  
Bonnie Van Lunen ◽  
Stacie I. Ringleb ◽  
James Onate
Keyword(s):  
Lower Extremity ◽  
Force Production ◽  
Peak Force ◽  
Maximum Strength ◽  
Time Constraints ◽  
Sports Performance ◽  
Force Development ◽  
Lower Extremity Strength ◽  
Optimal Health ◽  
And Performance

The ability to produce force rapidly and to maintain it is essential to sports performance. Although rapid force production and endurance are indispensable characteristics of optimal health and performance, assessing these qualities of strength is difficult because of clinician time constraints. The purpose of this study was to determine if peak force is a predictor of rate of force production and strength endurance. The results indicated peak force is a predictor of rate of force development, but not strength endurance. Clinicians should assess both maximum strength and endurance to gain a more complete picture of lower extremity strength deficits.

scholarly journals Biomass and Sugar Content of Some Varieties of Sorghum (Sorghum Bicolor L. Moench) on Dry Land Forest as Feedstock Bioethanol

2018 ◽  
Vol 164 ◽  
pp. 01035 ◽  
Author(s):  
Praptiningsih Gamawati Adinurani ◽  
Sri Rahayu ◽  
Luluk Sulistiyo Budi ◽  
Anggi Nindita ◽  
Peeyush Soni ◽  
...  
Keyword(s):  
Biomass Production ◽  
Block Design ◽  
Sugar Content ◽  
Sustainable Use ◽  
Dry Weight ◽  
Raw Material ◽  
Dry Land ◽  
Randomized Complete Block Design ◽  
High Sugar Content ◽  
Selection Of

The possibility of sustainable use of sorghum as raw material for bioethanol needs to be supported by evaluation and selection of sorghum varieties for high biomass production and sugar content. An experiment was conducted on forest dry land , altitude 63 m asl. This research aimed to determine the interaction of sorghum varieties and mycorrhiza on biomass production and the high sugar content. The experiment was a two factor (varieties and dosage of mycorrhiza plus) in a randomized complete block design with three replications. The varieties were Suri 3, Kawali, Super 2, Suri 4. Dosage of mycorrhiza plus (5, 10, 15) g per plant. The interaction only significant on a number of internodes and bagasse. There are no effects of dosages mycorrhiza plus, however, varieties of sorghum have significant effects on many variables measured. The highest amount of biomass include the stem height (301.28 cm), stem Dry Weight (DW) is 23.48 t ha-1, leaf DW (4.65 t ha-1), panicle DW (11.35 t ha-1) and biomass DW (39.98 t ha-1) were obtained in varieties Super 2. Sugar content (16.93 %) was obtained in varieties Suri 3 and juice production (2 742.86 L ha-1) in varieties Suri 4.

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