The Neuromuscular Qualities of Higher- and Lower-Level Mixed-Martial-Arts Competitors

2017 ◽  
Vol 12 (5) ◽  
pp. 612-620 ◽  
Author(s):  
Lachlan P. James ◽  
Emma M. Beckman ◽  
Vincent G. Kelly ◽  
G. Gregory Haff
Keyword(s):  
Martial Arts ◽  
Bench Press ◽  
Isometric Force ◽  
Average Power ◽  
Dynamic Strength ◽  
Upper Body ◽  
Whole Body ◽  
Lower Body ◽  
Mixed Martial Arts ◽  
Body Dynamic

Purpose:To determine whether the maximal strength, impulse, and power characteristics of competitive mixed-martial-arts (MMA) athletes differ according to competition level.Methods:Twenty-nine male semiprofessional and amateur MMA competitors were stratified into either higher-level (HL) or lower-level (LL) performers on the basis of competition grade and success. The 1-repetition-maximum (1RM) squat was used to assess lower-body dynamic strength, and a spectrum of impulse, power, force, and velocity variables were evaluated during an incremental-load jump squat. In addition, participants performed an isometric midthigh pull (IMTP) and 1RM bench press to determine whole-body isometric force and upper-body dynamic strength capabilities, respectively. All force and power variables were expressed relative to body mass (BM).Results:The HL competitors produced significantly superior values across a multitude of measures. These included 1RM squat strength (1.84 ± 0.23 vs 1.56 ± 0.24 kg BM; P = .003), in addition to performance in the incremental-load jump squat that revealed greater peak power (P = .005–.002), force (P = .002–.004), and velocity (P = .002–.03) at each load. Higher measures of impulse (P = .01–.04) were noted in a number of conditions. Average power (P = .002–.02) and velocity (P = .01–.04) at all loads in addition to a series of rate-dependent measures were also superior in the HL group (P = .005–.02). The HL competitors’ 1RM bench-press values approached significantly greater levels (P = .056) than the LL group’s, but IMTP performance did not differ between groups.Conclusions:Maximal lower-body neuromuscular capabilities are key attributes distinguishing HL from LL MMA competitors. This information can be used to inform evidenced-based training and performance-monitoring practices.

Recognition and prediction of driver’s whole body posture model

2022 ◽  
pp. 095440702110686
Author(s):  
Jun Wu ◽  
Jian Liu ◽  
Xiuyuan Li ◽  
Lingbo Yan ◽  
Libo Cao ◽  
...  
Keyword(s):  
Regression Model ◽  
Body Posture ◽  
Upper Body ◽  
Whole Body ◽  
Lower Body ◽  
Key Factor ◽  
Upper Body Posture ◽  
Spatial Coordinates ◽  
Posture Prediction ◽  
Connection Length

The driver’s whole-body posture at the time of a collision is a key factor in determining the magnitude of injury to the driver. However, current researchs on driver posture models only consider the upper body posture of the driver, and the lower body area which is not perceived by sensors is not studied. This paper investigates the driver’s posture and establishes a 3D posture model of the driver’s whole body through the application of machine vision algorithms and regression model statistics. This study proposes an improved Kinect-OpenPose algorithm for identifying the 3D spatial coordinates of nine keypoints of the driver’s upper body. The posture prediction regression model of four keypoints of the lower body is established by conducting volunteer posture acquisition experiments on the developed simulated driving seat and analyzing the volunteer posture data through using the principal components of the upper body keypoints and the seat parameters. The experiments proved that the error of the regression model in this paper is minor than that of current studies, and the accuracy of the keypoint location and the keypoint connection length of the established driver whole body posture model is high, which provides implications for future studies.

scholarly journals The Relationship between Isometric Force-Time Characteristics and Dynamic Performance: A Systematic Review

Sports ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 63 ◽  
Author(s):  
Danny Lum ◽  
G. Gregory Haff ◽  
Tiago M. Barbosa
Keyword(s):  
Isometric Force ◽  
Dynamic Performance ◽  
Lower Limbs ◽  
Upper Body ◽  
Original Research ◽  
Dynamic Performances ◽  
Time Variables ◽  
Force Time ◽  
The Relationship ◽  
Body Dynamic

The purpose of this article was to review the data on the relationship between multi-joint isometric strength test (IsoTest) force-time characteristics (peak force, rate of force development and impulse) and dynamic performance that is available in the current literature. Four electronic databases were searched using search terms related to IsoTest. Studies were considered eligible if they were original research studies that investigated the relationships between multi-joint IsoTest and performance of dynamic movements; published in peer-reviewed journals; had participants who were athletes or active individuals who participate in recreational sports or resistance training, with no restriction on sex; and had full text available. A total of 47 studies were selected. These studies showed significant small to large correlations between isometric bench press (IBP) force-time variables and upper body dynamic performances (r2 = 0.221 to 0.608, p < 0.05) and significant small to very large correlation between isometric squat (ISqT) (r2 = 0.085 to 0.746, p < 0.05) and isometric mid-thigh pull (IMTP) (r2 = 0.120 to 0.941, p < 0.05) force-time variables with lower body dynamic performances. IsoTest force-time characteristics were shown to have small to very large correlations with dynamic performances of the upper and lower limbs as well as performance of sporting movements (r2 = 0.118 to 0.700, p < 0.05). These data suggest that IsoTest force-time characteristics provide insights into the force production capability of athletes which give insight into dynamic performance capabilities.

Skeletal muscle mass and distribution in 468 men and women aged 18–88 yr

2000 ◽  
Vol 89 (1) ◽  
pp. 81-88 ◽  
Author(s):  
Ian Janssen ◽  
Steven B. Heymsfield ◽  
ZiMian Wang ◽  
Robert Ross
Keyword(s):  
Skeletal Muscle ◽  
Gender Differences ◽  
Body Weight ◽  
Upper Body ◽  
Whole Body ◽  
Lower Body ◽  
Large Measure ◽  
Imaging Protocol ◽  
Men And Women ◽  
Magnetic Resonance Imaging Protocol

We employed a whole body magnetic resonance imaging protocol to examine the influence of age, gender, body weight, and height on skeletal muscle (SM) mass and distribution in a large and heterogeneous sample of 468 men and women. Men had significantly ( P < 0.001) more SM in comparison to women in both absolute terms (33.0 vs. 21.0 kg) and relative to body mass (38.4 vs. 30.6%). The gender differences were greater in the upper (40%) than lower (33%) body ( P < 0.01). We observed a reduction in relative SM mass starting in the third decade; however, a noticeable decrease in absolute SM mass was not observed until the end of the fifth decade. This decrease was primarily attributed to a decrease in lower body SM. Weight and height explained ∼50% of the variance in SM mass in men and women. Although a linear relationship existed between SM and height, the relationship between SM and body weight was curvilinear because the contribution of SM to weight gain decreased with increasing body weight. These findings indicate that men have more SM than women and that these gender differences are greater in the upper body. Independent of gender, aging is associated with a decrease in SM mass that is explained, in large measure, by a decrease in lower body SM occurring after the fifth decade.

Biology of upper-body and lower-body adipose tissue—link to whole-body phenotypes

2014 ◽  
Vol 11 (2) ◽  
pp. 90-100 ◽  
Author(s):  
Fredrik Karpe ◽  
Katherine E. Pinnick
Keyword(s):  
Adipose Tissue ◽  
Upper Body ◽  
Whole Body ◽  
Lower Body

scholarly journals Effects of Supplementation of a Pre-workout on Power Maintenance in Lower Body and Upper Body Tasks in Women

2019 ◽  
Vol 4 (2) ◽  
pp. 18 ◽  
Author(s):  
Michael Timothy Lane ◽  
Mark Travis Byrd ◽  
Zachary Bell ◽  
Tyler Hurley
Keyword(s):  
High Intensity ◽  
Bench Press ◽  
Vertical Jump ◽  
Power Production ◽  
Upper Body ◽  
Maximal Velocity ◽  
Lower Body ◽  
Fat Percentage ◽  
Double Blind ◽  
Jump Performance

Currently there is a lack of research into how women respond to pre-workout supplementation. The effects of supplements on exercise performance in women, specifically to power, must be performed. This study investigated the effects of supplementation on power production and maintenance during a high-intensity cycle ergometry sprint performance, vertical jump performance, and bench press performance in women. It also investigated the effects of supplementation on power production and the maintenance of upper and lower body tasks in women. A total of 23 females (22.9 ± 3.6 years, 175.6 ± 6.5 cm, 86.9 ± 15.1 kg, 19.1 ± 8.4 body fat percentage (BF%) (mean ± std. dev.)) were familiarized with the testing protocol and maximal bench press performances were attained (49.5 ± 15.4kg). Utilizing a double-blind crossover design, subjects completed three trials of: Five countermovement vertical jumps, a high-intensity cycle sprint protocol, which consisted of 10 maximal, five second cycle ergometer sprints. Subjects performed a velocity bench press test, utilizing 80% of their predetermined one repetition maximum (1RM) for 10 sets of three repetitions for maximal speed. For 20 min prior to each trial, the subjects ingested, in a randomized order, a pre-workout supplement (Supp), placebo+150 mg caffeine (Caff), or a placebo (PL). Peak power (PP), mean power (MP), and minimum power (MNP) were recorded for each sprint. Maximal velocity from each set was also recorded. Bike sprint and bench press data were normalized to the placebo trial for analysis. Blood lactate (bLa−) was measured immediately prior to each testing session, within 2 min of the completion of the last cycle sprint and following the bench press test. Bike sprint and bench press testing showed no significant differences through the testing sessions, but did significantly decline over test battery (p < 0.05). Vertical jump performance and lactate levels were not significantly different. Supplementation with a pre-workout supplement or placebo with caffeine 20 min prior to participation showed no positive benefits to performance in female participants.

scholarly journals Validation and Reliability of a Novel Test of Upper Body Isometric Strength

2015 ◽  
Vol 47 (1) ◽  
pp. 189-195 ◽  
Author(s):  
David Bellar ◽  
Lena Marcus ◽  
Lawrence W. Judge
Keyword(s):  
Bench Press ◽  
Isometric Force ◽  
Body Height ◽  
Isometric Strength ◽  
Upper Body ◽  
Outcome Variable ◽  
Good Reliability ◽  
Strength Assessment ◽  
College Age ◽  
Body Strength

AbstractThe purpose of the present investigation was to examine the association of a novel test of upper body isometric strength against a 1RM bench press measurement. Forty college age adults (n = 20 female, n = 20 male; age 22.8 ± 2.8 years; body height 171.6 ± 10.8 cm; body mass 73.5 ± 16.3 kg; body fat 23.1 ± 5.4%) volunteered for the present investigation. The participants reported to the lab on three occasions. The first visit included anthropometric measurements and familiarization with both the upper body isometric test and bench press exercise. The final visits were conducted in a randomized order, with one being a 1RM assessment on the bench press and the other consisting of three trials of the upper body isometric assessment. For the isometric test, participants were positioned in a “push-up” style position while tethered (stainless steel chain) to a load cell (high frequency) anchored to the ground. The peak isometric force was consistent across all three trials (ICC = 0.98) suggesting good reliability. Multiple regression analysis was completed with the predictors: peak isometric force, gender, against the outcome variable 1RM bench press. The analysis resulted in a significant model (r2 = 0.861, p≤0.001) with all predictor variables attaining significance in the model (p<0.05). Isometric peak strength had the greatest effect on the model (Beta = 5.19, p≤0.001). Results from this study suggest that the described isometric upper body strength assessment is likely a valid and reliable tool to determine strength. Further research is warranted to gather a larger pool of data in regard to this assessment.

Effects of Sitting and Standing Work Postures on Short-Term Typing Performance and Discomfort

2016 ◽  
Vol 60 (1) ◽  
pp. 460-464 ◽  
Author(s):  
Gourab Kar ◽  
Alan Hedge
Keyword(s):  
Repeated Measures ◽  
Upper Body ◽  
Whole Body ◽  
Body Region ◽  
Lower Body ◽  
Analog Scale ◽  
Short Term ◽  
Work Posture ◽  
Body Discomfort ◽  
Typing Task

The study evaluated effects of sitting and standing work postures on objective short-term computer typing performance and perceived discomfort. A randomized, repeated measures, study design was used to assess typing performance and perceived discomfort for 12 participants on a 15-minute computer-typing task. Typing performance was measured by number of characters typed and number of errors. Perceived discomfort was measured for the whole body, as well as for upper body and lower body, using a visual analog scale. Results suggest that for a short-term computer typing task, compared to a sitting work posture a standing work posture leads to fewer typing errors without impacting typing speed. Overall levels of perceived discomfort for the whole body are similar for sitting and standing work postures. However, for perceived discomfort there is an interaction of work posture and body region - upper body discomfort is higher in the sitting work posture while lower body discomfort is higher in the standing work posture.

scholarly journals Physiological Aspects and Injuries in Mixed Martial Arts

2019 ◽  
Vol 59 (1) ◽  
pp. 1-12
Author(s):  
Petr Schlegel ◽  
Adam Křehký
Keyword(s):  
Martial Arts ◽  
Upper Body ◽  
Training Methods ◽  
Mixed Martial Arts ◽  
Metabolic Markers ◽  
Injury Rates ◽  
Performance Requirements ◽  
Body Strength ◽  
Upper Body Strength

Summary Mixed Martial Arts (MMA) has become an independent sport discipline with its own distinctive aspects. It can no longer be perceived as before, as a compilation of other martial arts. MMA shows originality in training methods, health aspects, performance requirements or even moral-volitional qualities. The aim of the paper is to analyse the physiological aspects of MMA in both training and combat loads, to discuss the issue of injuries in MMA and to provide a comparison with other martial arts. Studies focusing directly on MMA wrestlers have been selected. These have included both amateur and professional athletes. The databases Pubmed, Scopus, Web of Science, and Scholar were used as sources. MMA ranks among sports with high-intensity workload, wrestlers achieve high levels of lactate and other metabolic markers. They need above-average aerobic capacity and perform well in upper body strength tests. Injury rates in MMA do not differ significantly from those in professional-level martial arts. Most injuries are associated with lacerations on the head. The requirements of extensive workload during performance must be reflected in training. Encouragement of aerobic and anaerobic endurance abilities in conjunction with optimum strength training seems crucial. It is essential to include prophylaxis as regards head concussions and strive for maximum safety of the sportsman during combat. Further research is required to confirm some of the conclusions, the limitations of which are due to the number and quality of the selected studies.

scholarly journals The onset time of balance control during walking is phase-independent, but the magnitude of the response is not

2019 ◽  
Author(s):  
Hendrik Reimann ◽  
Tyler Fettrow ◽  
David Grenet ◽  
Elizabeth D. Thompson ◽  
John J. Jeka
Keyword(s):  
Nervous System ◽  
Gait Cycle ◽  
Center Of Pressure ◽  
Body Movement ◽  
Reaction Force ◽  
The Body ◽  
Upper Body ◽  
Whole Body ◽  
Lower Body ◽  
The Central Nervous System

AbstractThe human body is mechanically unstable during walking. Maintaining upright stability requires constant regulation of muscle force by the central nervous system to push against the ground and move the body mass in the desired way. Activation of muscles in the lower body in response to sensory or mechanical perturbations during walking is usually highly phase-dependent, because the effect any specific muscle force has on the body movement depends upon the body configuration. Yet the resulting movement patterns of the upper body after the same perturbations are largely phase-independent. This is puzzling, because any change of upper-body movement must be generated by parts of the lower body pushing against the ground. How do phase-dependent muscle activation patterns along the lower body generate phase-independent movement patterns of the upper body? We hypothesize that in response to a perceived threat to balance, the nervous system generates a functional response by pushing against the ground in any way possible with the current body configuration. This predicts that the changes in the ground reaction force patterns following a balance perturbation should be phase-independent. Here we test this hypothesis by disturbing upright balance using Galvanic vestibular stimulation at three different points in the gait cycle. We measure the resulting changes in whole-body center of mass movement and the location of the center of pressure of the ground reaction force. We find that the whole-body balance response is not phase-independent as expected: balance responses are initiated faster and are smaller following a disturbance late in the gait cycle. Somewhat paradoxically, the initial center of pressure changes are larger for perturbations late in the gait cycle. The onset of the center of pressure changes however, does not depend on the phase of the perturbation. The results partially support our hypothesis of a phase-independent functional balance response underlying the phase-dependent recruitment of different balance mechanisms at different points of the gait cycle. We conclude that the central nervous system recruits any available mechanism to push against the ground to maintain balance as fast as possible in response to a perturbation, but the different mechanisms do not have equal strength.

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