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Background Well defined constitutional parameters support the physical fatigue resistance in handball to maintain the performance level for the majority of actions. Ideal constitutional conditions are necessary to achieve these physiological advantages in handball. But limited knowledge exists about the upper body posture or the postural control in correlation to the Body Mass Index (BMI), playing years, playing position and throwing arm in professional male handball. Methods Ninety-one male handball players participate (24.1 ± 5.9 years; playing experience 16.6 ± 5.7 years). A three-dimensional back scanner and a pressure measuring plate were used. Results Correlations between BMI and upper body posture and postural control were not significant. Same counts for the comparison between the left and right throwing arm according to upper body posture and postural control (p ≥ 0.05). Correlations between the years of playing can be found at pelvis height (p ≤ 0.04) and for the length of the Center of Pressure (CoP) (p ≤ 0.01). Wing players are 6.5–8.5 cm smaller. The playing position is independently of BMI, age or upper body posture (p ≥ 0.05). Backcourt players have a higher load of the left and a lower load of the right foot compared to wing players (p ≤ 0.001). Left-right comparison (p ≤ 0.001/ 0.01) can be seen in pivot player (covered area), backcourt player (weight distribution left/right [rear] foot), wing player (weight and force distribution left/right foot, covered area). Conclusion Goalkeeper, Backcourt and pivot players are taller and heavier than wing players. These physiological demands are not detectable in the upper body posture and slightly in postural control. Wing players have the most asymmetric load distribution and the longest length of CoP. Since goalkeepers do not differ from pivot or backcourt players, this can be lead back to the same training.

Objectives Recent research has revealed that low volume resistance ‘priming’ exercise may improve neuromuscular performance when completed within 48 h before competition. The aim of this study was to investigate the current prevalence and application of this strategy by practitioners in sport. Design This study surveyed practitioners who were currently programming and/or prescribing resistance training programs for high performance athletes. Methods Sixty-nine practitioners completed the online survey relating to their perceptions of resistance priming exercise strategies and the training methods prescribed in the days prior to competition. Results Fifty-one percent of respondents currently prescribed priming exercise. Of the practitioners who prescribed this strategy, most respondents (59%) prescribed this session within 8 h of competition. Sessions typically included 2–3 upper body and lower body exercises (mean = 2.5 ± 0.7 and 2.1 ± 0.6 respectively), usually involving both loaded and unloaded activities. Large variations in exercise selection were reported, however, unloaded jumps (87%), loaded jumps (60%) and bench press (56%) were commonly prescribed. A low volume of sets (mean = 2.8 ± 0.9) and repetitions (mean = 3.8 ± 1.3) were used during these sessions. Lastly, various resistance loading strategies were prescribed, ranging from unloaded activities to heavy loaded exercises performed at ≥85% 1RM. Conclusions Priming exercise is currently prescribed by many practitioners to prepare athletes for competition. A wide range of priming exercise methods are used, despite limited evidence supporting these methods. Future research should examine the effects of the various priming methods which are currently applied in practice.

Intradialytic cycling is a widely used workout mode, whereas added benefit of other exercise modalities remains unknown. This is the first randomised controlled trial on the effects and sustainability of functional training and counselling in addition to intradialytic cycling. Patients were randomly assigned to a kinesiologist-guided functional training in addition to intradialytic cycling (n = 20, experimental group) or intradialytic cycling only (n = 20, control group) over 16 weeks. The experimental group attended predialysis functional exercise in the first eight weeks and afterward performed functional training at home for the next eight weeks. The primary study endpoint was 10-repetition-sit-to-stand test time at eight weeks: at this test, the experimental group improved significantly better than controls (−4.5 ± 1.9 s, 95%CI −8.4 to −0.7; P = 0.021), which was maintained at week 16 (−4.7 ± 2.1 s, 95%CI −9.0 to −0.3; P = 0.037). At week 8, the experimental group significantly outperformed controls also at handgrip strength (P = 0.004), lower body flexibility test (P

This study consisted of 10 female students with Cobb’s angle of 10 degrees or more to investigate the effects of 12 weeks gyrotonic exercise program on body composition, Cobb’s angle and lumbar muscle strength in adolescents with idiopathic scoliosis. The gyrotonic exercise program was conducted twice a week for about 60 minutes, and was applied to four programs such as Arch-curl series, Hamstring series, Upper body series, and Abdominal series. Gradually changing with increasing. The results of this research is as follows: 1) After 12 weeks of gyrotonic exercise program, body composition were a significantly increase in body weight (p＜.05) and lean body mass (p＜.05). 2) After 12 weeks of gyrotonic exercise program was a significantly decrease in Cobb’s angle (p＜.01). 3) After 12 weeks of gyrotonic exercise program was a significantly increase in lumbar muscle strength (p＜.05). These results confirm that the gyrotonic exercise program has a positive effect on the improvement of idiopathic scoliosis and there is considered to be an effective method for the prevention and exercise treatment of idiopathic scoliosis.

Venckunas, T, Bruzas, V, Stasiulis, A, Snieckus, A, Mockus, P, and Kamandulis, S. Cardiorespiratory responses to specific and non-specific exercise in high-profile amateur boxers. J Strength Cond Res 36(3): 717-722, 2022-Our aim was to compare cardiorespiratory responses in 3 types of all-out exercises (upper body, lower body, and punching) in well-trained boxers and peak heart rate (HR) in these tests with HR response to competitive Olympic boxing. On 4 separate occasions, 11 male amateur boxers performed: (a) progressive treadmill running to exhaustion; (b) progressive arm cranking to failure; (c) progressive bag punching to maximal exertion; and (d) competitive boxing fight (3 × 3 minutes format). Expired gas and HR were measured in all tasks except in the full-contact competitive fight where only HR was recorded. Peak oxygen uptake (55.3 ± 5.9 ml·kg-1·min-1) was highest during treadmill running. Peak respiratory exchange ratio was highest during bag punching (1.26 ± 0.09), but did not differ between arm cranking and running. Peak HR of the boxing fight (197.7 ± 5.9 b·min-1) did not differ from that of running (196.5 ± 8.7 b·min-1), but was smaller in arm cranking (179.8 ± 9.2) and bag punching (184.1 ± 12.2 b·min-1). The correlation coefficients between peak HR achieved during competitive fighting and that achieved during running, arm cranking and bag punching were 0.720 (p = 0.013), 0.597 (p = 0.052), and 0.702 (p = 0.035), respectively. In conclusion, in high-profile amateur boxers, running evoked a higher cardiorespiratory activation than arm cranking or bag punching, whereas punching elicited the highest input of anaerobic glycolysis. Peak HR of competitive fighting was the same as during running and much higher than during arm cranking or bag punching.

Isometric strength tests are gaining popularity in recent years. However, no study has validated any isometric strength tests to assess upper body pulling ability. The aim of this study was to investigate the validity and reliability of isometric prone bench pull. Twenty-three resistance trained athletes (age: 26±4 years, height: 1.75±0.07 m, body mass: 78.6±11.5 kg) were required to perform prone bench pull 1 repetition maximum and isometric prone bench pull tests during the familiarization and actual testing sessions. Isometric prone bench pull was performed at 90° and 120° elbow angles. Peak force and rate of force development measures were highly reliable with intra-correlation coefficient between 0.881–0.987. Peak force obtained from isometric prone bench pull at both elbow angles showed large correlations to prone bench pull 1 repetition maximum (r=0.833–0.858, p

Summary Our purposes were to examine the fitness characteristics of padel players and to determine differences in physical performance regarding players’ competitive level. Eighteen non-professional male padel players were divided according to their competitive level (low-level vs. high-level). Players completed a 2-days evaluation process including body composition, groundstroke padel accuracy, upper body power, handgrip strength, dynamic balance, agility and speed and cardiovascular fitness. Heart rate recovery after 60 s and dynamic balanced were identified as the most determinant factors in padel performance. High-level players reported a better heart rate recovery after 60 s. Low-level players with better heart rate recovery showed better groundstroke accuracy. Dynamic balance in anterior directions was alarmingly poor in both high- and low-level players (mean

Shanidar Cave in Iraqi Kurdistan became an iconic Palaeolithic site following Ralph Solecki's mid twentieth-century discovery of Neanderthal remains. Solecki argued that some of these individuals had died in rockfalls and—controversially—that others were interred with formal burial rites, including one with flowers. Recent excavations have revealed the articulated upper body of an adult Neanderthal located close to the ‘flower burial’ location—the first articulated Neanderthal discovered in over 25 years. Stratigraphic evidence suggests that the individual was intentionally buried. This new find offers the rare opportunity to investigate Neanderthal mortuary practices utilising modern archaeological techniques.

Basketball activity classification can help document players’ statistics, allow coaches, trainers and the medical team to quantitatively supervise players’ physical exertion and optimize training strategy, and further help prevent potential injuries. Traditionally, sports activity classification was done by manual notational, or through multi-camera systems or motion sensing technology. These methods were often erroneous and limited by space. This study presents a basketball activity classification model based on Dynamic Time Warping (DTW) and body kinematic measures. Twenty participants, including 10 experienced players and 10 novice players, were involved in an experimental study. The experienced and novice players differed in their years of playing basketball. Four basketball movements, including shooting, passing, dribbling, and lay-up were classified by kinematic measures. The results indicate that the proposed model can successfully classify different basketball movements with high accuracy and efficiency. Specifically, with the resultant acceleration of the hand, this model can achieve classification precision, recall, and specificity up to 0.984, 0.983 and 0.994, respectively. Findings from this study supported the feasibility of using DTW in real-time sports activity classification and provided insights into the optimal sensor placement for basketball activity classification applications.

We examined the geography of top achievements in weightlifting in the Olympic Games for men (1992-2016), and women (2000-2016). Geographic origins of men are restricted to countries with a salient center around the Balkan and the Caucasus areas. This is especially evident for weightlifters in the upper body weight categories. Top achievements of women are more widely spread geographically, yet with clustering in the south-eastern part of Asia. Data on participation in the Olympic Games suggest that this unbalanced geographical spread of men is unlikely to be explained by cultural preferences but rather by specific physical adaptations. This conclusion receives further support from considering weight to height ratio of athletes winning gold medals relative to the average in the general population.

Biomechanics deals with the study of the mechanical aspects of the biological objects. The humerus bone is the longest bone of the upper body. In this study, we apply different loads on the humerus bone fixing the proximal (upper end) and applying varying loads on the distal side (lower end) and note down the displacement and maximum stress occurring at different loads for different materials. From this we come to know about the maximum stress at which the bone fails. Model is prepared using ITK-Snap software. MSC Patran software is used for pre processing and post processing, whereas MSC Nastran is used as solver. Analysis is carried out for three different material, natural bone, AZ31, and CP-Ti. It is found that at 85 N natural bone fractures at middle portion of the bone (Deltoid Tuberosity). Bone implants made up of AZ31 materials will be absorbed by the body and no further surgery is required. The stress and displacement are comparatively minimum for this material and it is light weight as compared to CP-Ti. The manufacturing cost is also minimal.

Lumbar loading causes increased intervertebral pressure and is an important factor in low back pain. However, it is difficult to quantitatively judge the actions that affect lumbar load and the magnitude of lumbar load increase. Low back pain occurs not only in the workplace but also during activities of daily living. Therefore, it is necessary to investigate the factors inducing low back pain by measuring movements in various planes and determining the magnitude of the lumbar load. Accordingly, the lumbar spine should be examined during various movements. Several studies have examined vertebral bodies in the anteflexion posture. However, the relationship between body flexion angle and vertebral body angle during lateral flexion and rotation remains unknown. In this study, we proposed an estimation method for changes in vertebral body angle during lateral flexion and rotation in the lumbosacral region using a wearable sensor system we previously developed. The accuracy of the proposed estimation method was evaluated and demonstrated using X-ray images.

Objectives: To assess the magnitude of change and association with variation in training load of two performance markers and wellbeing, over three pre-season training blocks, in elite rugby union athletes. Design: Observational. Methods: Twenty-two professional players (age 25 ± 5 years; training age 6 ± 5 years; body mass, 99 ± 13 kg; stature 186 ± 6 cm) participated in this study, with changes in lower (CMJ height) and upper body (bench press mean speed) neuromuscular function and self-reported wellbeing (WB) assessed during an 11-week period. Results: There was a small increase in CMJ height (0.27, ±0.17 – likely substantial; standardised effect size, ±95% confidence limits – magnitude-based inference) (p = 0.003), bench press speed (0.26, ±0.15 – likely substantial) (p = 0.001) and WB (0.26, ±0.12 – possibly substantial) (p < 0.0001) across the pre-season period. There was a substantial interaction in the effect of training load on these three variables across the three training phases. A two-standard deviation (2SD) change in training load was associated with: a small decrease in CMJ height during the power phase (−0.32, ±0.19 – likely substantial) (p = 0.001); a small reduction in bench press speed during the hypertrophy phase (−0.40, ±0.32 – likely substantial) (p = 0.02); and a small reduction in WB during the strength phase (−0.40, ±0.24 – very likely substantial) (p < 0.0001). The effects of changes in training load across other phases were either likely trivial, only possibly substantial, or unclear. Conclusions: The effect of training load on performance can vary both according to the type of training stimulus being administered and based on whether upper- or lower-body outcomes are being measured.

Purpose: Studies have indicated upper body involvement during football, provoking long-term muscular adaptations. This study aimed at examining the acute metabolic response in upper and lower body skeletal muscle to football training organized as small-sided games (SSG). Methods: Ten healthy male recreational football players [age 24 ± 1 (± SD) yrs; height 183 ± 4 cm; body mass 83.1 ± 9.7 kg; body fat 15.5 ± 5.4%] completed 1-h 5v5 SSG (4 × 12 min interspersed with 4-min recovery periods). Muscle biopsies were obtained from m. vastus lateralis (VL) and m. deltoideus (DE) pre- and post-SSG for muscle glycogen and metabolite analyses. Blood lactate samples were obtained at rest, middle and end of the SSG. Results: Muscle glycogen in VL decreased (P < 0.01) by 21% and tended (P = 0.08) to decrease in DE by 13%. Muscle lactate increased in VL (117%; P < 0.001) and DE (81%; P < 0.001) during the game, while blood lactate rose threefold. Muscle ATP and PCr were unaltered, but intermuscular differences were detected for ATP at both time points (P < 0.001) and for PCr at pre-SSG (P < 0.05) with VL demonstrating higher values than DE, while muscle creatine rose in VL (P < 0.001) by 41% and by 22% in DE (P = 0.02). Baseline citrate synthase maximal activity was higher (P < 0.05) in VL compared to DE, whereas baseline muscle lactate concentration was higher (P < 0.05) in DE than VL. Conclusion: The upper body may be extensively involved during football play, but besides a rise in muscle lactate in the deltoideus muscle similar to the leg muscles, the present study did not demonstrate acute metabolic changes of an order that may explain the previously reported training effect of football play in the upper extremities.

This paper describes a semi-active assistive exoskeleton for upper-body motion assistance. The exoskeleton combines a passive shoulder exoskeleton and an active elbow joint unit, which can achieve both passive gravity compensation and also active assistance to carrying and sit-to-stand motion. The design, sensing and control are introduced, with preliminary test results performed.

BackgroundSupracondylar humerus fractures (SCHF) are the most common fractures sustained following a fall onto an outstretched hand among healthy children, and one of the leading causes of hospital admission and surgical intervention. The aim of this study was to examine SCHF occurring at public play spaces—particularly to determine whether or not the playground equipment implicated in injurious falls aligned with Canadian playground safety standards.MethodsCases of children who attended the provincial paediatric orthopaedic clinic following SCHF at a public playground between April 2017 and October 2019 were included in the study. A research assistant visited each playground to measure the play structure type and dimensions, height of the equipment at the point from which the child fell and the type and depth of the surface material, and compare measurements to the 2016 safety standards. Child demographics and injury classification were also noted. Descriptive statistics were calculated and a scatterplot of fall height and surface depth was generated.ResultsForty-three sites, representing 47 SCHF cases (18 female, 29 male), were included in the final analysis. Fourteen children sustained type 1 fracture, 23 had type 2 fracture and the remaining 10 had type 3 fracture. Five children with type 2 fracture and all 10 children with type 3 fracture required surgery. The majority of sites had engineered wood fibre surfacing, with surfacing at 35 sites being less than 300 mm deep. Twenty-six play structures were upper body equipment (ie, monkey bars or similar), seven were track rides, five were rotating structures and the rest comprised a variety of classified and unclassified structures. Twenty-seven children fell from a height exceeding 2 m.ConclusionsThe majority of SCHF cases occurred at playgrounds with insufficient surface depth and/or non-compliant equipment. Upper body equipment, track rides and rotating play structures were of particular concern, as the children fell from heights exceeding the recommended standard, likely reflecting the degradation and compaction of the surfacing material over time.

Purpose Upper-body exercise performed in a cold environment may increase cardiovascular strain, which could be detrimental to patients with coronary artery disease (CAD). This study compared cardiovascular responses of CAD patients during graded upper-body dynamic and static exercise in cold and neutral environments. Methods 20 patients with stable CAD performed 30 min of progressive dynamic (light, moderate, and heavy rating of perceived exertion) and static (10, 15, 20, 25 and 30% of maximal voluntary contraction) upper body exercise in cold (− 15 °C) and neutral (+ 22 °C) environments. Heart rate (HR), blood pressure (BP) and electrocardiographic (ECG) responses were recorded and rate pressure product (RPP) calculated. Results Dynamic-graded upper-body exercise in the cold increased HR by 2.3–4.8% (p = 0.002–0.040), MAP by 3.9–5.9% (p = 0.038–0.454) and RPP by 18.1–24.4% (p = 0.002–0.020) when compared to the neutral environment. Static graded upper-body exercise in the cold resulted in higher MAP (6.3–9.1%; p = 0.000–0.014), lower HR (4.1–7.2%; p = 0.009–0.033), but unaltered RPP compared to a neutral environment. Heavy dynamic exercise resulted in ST depression that was not related to temperature. Otherwise, ECG was largely unaltered during exercise in either thermal condition. Conclusions Dynamic- and static-graded upper-body exercise in the cold involves higher cardiovascular strain compared with a neutral environment among patients with stable CAD. However, no marked changes in electric cardiac function were observed. The results support the use of upper-body exercise in the cold in patients with stable CAD. Trial registration Clinical trial registration NCT02855905 August 2016.

INTRODUCTION: The purpose of the study was to evaluate the thermal protection provided by a 2–3 mm surfing wet suit during at least two hours of fin diving in shallow water with a temperature of 16–20°C. We examined the effect of wearing the suit while diving in cold water on cognitive performance, muscle strength, and hand motor function. METHODS: Subjects were six male well-trained rebreather divers, 19–23 years old, acclimatised to cold. They attended the laboratory on three separate occasions, when we conducted the experiment at one of three temperatures, 16, 18, and 20°C. Core temperature (gastrointestinal system), skin temperature, oxygen consumption, and cold perception were evaluated during the test. Before and immediately after the dives, subjects performed a series of cognitive, manual dexterity, and muscle strength tests. RESULTS: Core temperature decreased by 0.35–0.81°C over the two hours at all three water temperatures. No subject reached a core temperature below 35°C. The decrease in upper body skin temperature during the two hour dive ranged between 5.97 and 8.41°C (P < 0.05). Two hours diving in 16–20°C water resulted in a significant increase in the time taken to perform the task of unlinking and reassembling four shackles (∼30% longer, P < 0.05). No effect was found on the cognitive or muscle strength tests. CONCLUSION: A 2–3 mm wet suit provides adequate thermal protection in trained and cold-acclimatised young males engaged in active diving in shallow water with a temperature of 16°C and above.

This project examined the interrelationships between power production and upper body kinematics during a series of medicine ball push-press (MBP-P) throws. Twenty-five regular weight trainers (body mass = 86 ± 10 kg) performed a series of ballistic vertical MBP-P throws at loads representing 5% and 10% of their assessed 5RM bench press. Throws were performed lying supine on a force platform (1 kHz) with upper body kinematics assessed using standard infra-red motion capture techniques (0.5 kHz). Gross measures of performance and power production such as peak vertical ball velocity (Vel

Successful interaction within the environment is contingent upon one’s ability to accurately perceive the extent over which they can successfully perform actions, known as action boundaries. Healthy young adults are accurate in estimating their action boundaries and can flexibly update them to accommodate stable changes in their action capabilities. However, there are conditions in which motor abilities are subject to variability over time such as in Parkinson’s disease (PD). PD impairs the ability to perform actions and can lead to variability in perceptual-motor experience, but the effect on the perceptions of their action boundaries remains unknown. This study investigated the influence of altered perceptual-motor experience during PD, on the perceptions of action boundaries for reaching, grasping, and aperture passing. Thirty participants with mild-to-moderate idiopathic PD and 26 healthy older adults provided estimates of their reaching, grasping, and aperture-passing ability. Participants’ estimates were compared with their actual capabilities. There was no evidence that individuals with PD’s perceptions were less accurate than those of healthy controls. Furthermore, there was some evidence for more conservative estimates than seen in young healthy adults in reaching (both groups) and aperture passing (PD group). This suggests that the ability to judge action capabilities is preserved in mild to moderate PD. Supplementary Information The online version contains supplementary material available at 10.3758/s13414-021-02340-y.

The use of ultrasound techniques has brought additional surgical knowledge to increase the accuracy and effectiveness of peripheral nerve stimulation in the treatment of chronic painful syndromes. In this chapter we will describe the use of ultrasound techniques for peripheral nerve stimulation in the upper body segment.

The purpose of this study was to meta-analyze the effects of yoga intervention on physical fitness in the elderly. The following databases were systematically searched in 25 March 2021: Cochrane, PubMed and Embase. A total of 656 papers was identified through key word combinations, finally, 12 studies were included in the meta-analysis. The main conclusions are as follows. First, yoga practice showed moderately positive effects on muscle strength, balance, mobility, and lower body flexibility, but had no significant effect on cardiorespiratory endurance and upper body flexibility. Second, sub-group analysis showed that subjects in their 60s and 70s and yoga practice for 9–12 weeks had a large positive effect on physical fitness. Yoga is a multimodal activity that improves muscle strength, balance, and flexibility in the elderly, and physical activity policies should continue to promote yoga as an activity that enhances physical and mental wellbeing in this population.

A recently developed compact 3 T (C3T) MRI scanner with high performance gradients [1, 2] has a dedicated radiofrequency (RF) transmit coil that exposes only the head, neck and a small portion of the upper body region during head-first scanning. Due to the unique coil geometry and patient positioning, the established SAR model used for a conventional whole-body scanner cannot be directly translated to the C3T. Here a specific absorption rate (SAR) estimation and validation framework was developed and used to implement a dedicated and accurate SAR prediction model for the C3T. Two different SAR prediction models for the C3T were defined and evaluated: one based on an anatomically derived exposed mass, and one using a fixed anatomical position located caudally to the RF coil to determine the exposed mass. After coil modeling and virtual human body simulation, the designed SAR prediction model was implemented on the C3T and verified with calorimetry and in vivo scan power monitoring. The fixed-demarcation exposed mass model was selected as appropriate exposed mass region to accurately estimate the SAR deposition in the patient on the C3T.

BackgroundFemales are reported to have a higher risk of musculoskeletal disorders than males. Repetitive motions can lead to muscle fatigue, which may play a mediator role in the development of musculoskeletal disorders. However, sex differences in adaptations to localized fatigue at different joints are poorly understood. We examined the sex-specific effects of fatigue location on shoulder, elbow and spinal joint angles, and angular variabilities during a repetitive pointing task.MethodsSeven males and ten females performed a 30-s standing repetitive pointing task with their right upper limb when they were non-fatigued (NF), elbow-fatigued (EF), shoulder-fatigued (SF) and trunk-fatigued (TF), while trunk and upper body tridimensional kinematic data was recorded. Joint angles and angular variabilities of shoulder, elbow, upper thoracic spine, lower thoracic spine, and lumbar spine were calculated.ResultsResults showed that shoulder angles changed the most after EF in males, but after SF in females. The similarities between sexes were that SF increased the variabilities at upper (lateral flexion: 0.15° greater than NF, rotation: 0.26° greater than all other conditions) and lower thoracic spine (lateral flexion: 0.13° greater than NF, rotation: averagely 0.1° greater than all other condition) in both sexes. TF altered upper thoracic spine variability (0.36° smaller than SF), lower thoracic spine angle (lateral flexion: 3.00° greater than NF, rotation: 1.68° greater than SF), and lumbar angle (averagely 1.8° smaller than all other conditions) in both sexes. However, females had greater lower thoracic spine angle (lateral flexion: 8.3° greater,p = 0.005) as well as greater upper (rotation: 0.53° greater,p = 0.006) and lower thoracic spine (rotation: 0.5° greater,p = 0.007; flexion: 0.6° greater,p = 0.014) angular variabilities than males.ConclusionsResults suggest that females’ fatigue responses focused on the trunk and spine. Results highlight a few sex differences in adapting to localized muscle fatigue, which may help explain how sex differences in repetitive motion-related injuries differ between joints.

Currently, the only mechanisms in place to help people stand up require the assistance of care staff and a strong upper body. We hypothesize that there is a valid mathematical model to predict the optimal lower limb stiffness and damping to predict the risk of falling. These found values can be used to create an adjustable device that can help people stand more easily on their own.

One repetition maximum (1RM) push-ups, based upon the load–velocity relationship, are able to predict the maximum upper body strength. The aim of the present study was to examine the relationship between the predicted 1RM push-up based upon the load–velocity relationship and swimming performance and kinematical variables in competitive swimmers. Thirty-three competitive male swimmers (age = 16.46 ± 0.59 years, body mass = 72.82 ± 8.41 kg, body height = 180.56 ± 5.69 cm) performed push-up exercises without a weight vest and with a 10, 20 and 30 kg weight vests. A load–velocity relationship was established as a product of the load and velocity of the push-up per participant, and the equation was used to establish a predicted 1RM. Our findings showed a predicted 1RM push-up of 82.98 ± 9.95 kg. Pearson correlations revealed a nearly perfect relationship between the 1RM push-up and the 25 or 50 m front crawl (r = −0.968, r = −0.955), and between 1RM push-up and the 25 or 50 m front crawl with arms (r = −0.955, r = x0.941). Similarly, our results revealed significant near-perfect correlations between 1RM push-up and kinematical variables (r = 0.93–0.96) except the stroke index, which had a large relationship (r = 0.56). This study suggests that swimming performance and kinematical variables are correlated with the predicted 1RM push-up. The 1RM push-up based upon the load–velocity relationship is a low cost and time-effective alternative for swimmers and coaches to predict maximum upper body strength to optimize swimming performance in short races.

The acquisition of postural control is an elaborate process, which relies on the balanced integration of multisensory inputs. Current models suggest that young children rely on an ‘en-block’ control of their upper body before sequentially acquiring a segmental control around the age of 7, and that they resort to the former strategy under challenging conditions. While recent works suggest that a virtual sensory environment alters visuomotor integration in healthy adults, little is known about the effects on younger individuals.Here we show that this coordination pattern is disrupted by an immersive virtual reality framework where a steering role is assigned to the trunk, which causes 6- to 8-year-olds to employ an ill-adapted segmental strategy. These results provide an alternate trajectory of motor development and emphasize the immaturity of postural control at these ages.

Objectives: The sit-to-stand (STS) transfer mobilizes an extended part of the kinematic chain throughout a postural phase characterized by a flexion of the trunk and a focal phase consisting of a whole-body extension. The aim of this study was to analyze the variations of the global muscular pattern and the biomechanical parameters in both phases, in relation with seat backrest inclination.Methods: Fifteen participants were asked to stand up from a seat with 5 backrest inclination settings and at 2 execution speeds. The ground reaction forces and the activity levels of fifteen muscles of the trunk and lower limbs were investigated.Results: Backrest-induced modifications were mainly observed in the postural phase: inclining the backrest backward increased the phase duration and the activity level of the sternocleidomastoideus and the rectus abdominis, while it reduced the activity of the tibialis anterior. It also allowed for an increased maximal anteroposterior velocity of the body center of mass. Higher execution speed led to increased and earlier muscular activities of many trunk and lower limbs muscles, predominantly in the postural phase.Discussion: Taken together, these results suggest that a greater backrest inclination increases the demand in the postural phase due to the increase of the upper body gravity torque about the ischial tuberosities, and requires an adaptation of muscular activity levels and timing, but with the same overall pattern. The kinetic energy gained during the longer excursion of the trunk may also require less activation of the lower limbs muscles involved in the generation of propulsive forces of the body.

The purpose of this article is to summarize research on the effects of CKC and OKC upper body resistance training on serve velocity. Practical applications of this research are discussed and examples of how these exercises can be implemented into a tennis player’s training program are provided.

Attention and awareness towards musculoskeletal disorders (MSDs) in the dental profession has increased considerably in the last few years. From recent literature reviews, it appears that the prevalence of MSDs in dentists concerns between 64 and 93%. In our clinical trial, we have assessed the dentist posture during the extraction of 90 third lower molars depending on whether the operator performs the intervention by the use of the operating microscope, surgical loupes, or with the naked eye. In particular, we analyzed the evolution of the body posture during different interventions evaluating the impact of visual aids with respect to naked eye interventions. The presented posture assessment approach is based on 3D acquisitions of the upper body, based on planar markers, which allows us to discriminate spatial displacements up to 2 mm in translation and 1 degree in rotation. We found a significant reduction of neck bending in interventions using visual aids, in particular for those performed with the microscope. We further investigated the impact of different postures on MSD risk using a widely adopted evaluation tool for ergonomic investigations of workplaces, named (RULA) Rapid Upper Limb Assessment. The analysis performed in this clinical trial is based on a 3D marker tracker that is able to follow a surgeon’s upper limbs during interventions. The method highlighted pros and cons of different approaches.

Although before-touch situations are essential to achieve natural touch interactions between people and robots, they receive less attention than after-touch situations. This study reports pre-touch reaction distance analysis results around touchable upper body parts, i.e., shoulders, elbows, and hands, based on human–human pre-touch interaction. We also analyzed the effects of gender, approach side, speed, and acclimation in modeling the pre-touch reaction distance, and found that the distance around the hands is smaller than the distance around the shoulders and elbows, and speed and acclimation affect the distance. On the other hand, gender and approach side do not significantly affect the pre-touch reaction distance. Finally, we implemented the results in a male-looking android and confirmed that it reacted toward pre-touch based on the obtained model.

We present a learning-based method for generating animated 3D pose sequences depicting multiple sequential or superimposed actions provided in long, compositional sentences. We propose a hierarchical two-stream sequential model to explore a finer joint-level mapping between natural language sentences and the corresponding 3D pose sequences of the motions. We learn two manifold representations of the motion –- one each for the upper body and the lower body movements. We evaluate our proposed model on the publicly available KIT Motion-Language Dataset containing 3D pose data with human-annotated sentences. Experimental results show that our model advances the state-of-the-art on text-based motion synthesis in objective evaluations by a margin of 50%.

Background: Sedentarism and inactivity are risk factors for the development of hypertension. Thus, the prevention of the natural process of biological and physiological aging of older women through physical exercise results in higher benefits in preventing cardiovascular diseases and can be a key factor for its treatment. Multicomponent exercise (METP) is a training method that may help older women with hypertension by improving their quality of life and their response to treatment. Methods: Twenty-eight older Caucasian women with hypertension (66.7 ± 5.3 years, 1.59 ± 0.11 m) performed a supervised METP program of nine months followed by three months of detraining (DT), and seventeen older women (68.2 ± 4.7 years, 1.57 ± 0.16 cm) with hypertension maintained their daily routine, without exercise. Blood pressure (BP), resting heart rate, and functional capacity (FC) were evaluated at the beginning and at the end of the program, and after three months of DT. Results: The ME program improved (p &lt, 0.05) systolic BP (−5.37%), diastolic BP (−5.67%), resting heart rate (−7.8%), agility (9.8%), lower body strength (27.8%), upper body strength (10.0%), and cardiorespiratory capacity (8.6%). BP and FC deteriorated after the DT period (p &lt, 0.05). Conclusion: Nine months of multicomponent exercise were sufficient to improve functional capacity and promote benefits in blood pressure, although was not sufficient to allow BP to reach the normal values of older women. The three month DT period without exercise caused the reversal of BP improvements but maintained the functional capacity of older women.

This study aims (a) to assess and compare the acute mechanical, physiological,and perceptual demands induced by a lower and upper body repeated powerability (RPA) protocols, and (b) to examine how the somatic maturation could predicttraining response in RPA. Thirteen young male basketball players (chronologicalage = 15.2±1.1 years; height = 173.8±9.5 cm; body mass = 71.7±18.3 kg) wereselected to perform the parallel Back Squat (BS), and Bench Press (BP) RPA protocols(3 blocks of 5 sets of 5 repetitions with 30 s and 3 min of passive recovery betweensets and blocks, respectively). Mean propulsive power (MPP), accelerometer-baseddata, cardio-respiratory data, blood lactate, rate of perceived exertion (RPE) and musclesoreness were recorded. Somatic maturation was estimated according to the Khamisand Roche method. On the BS protocol, the mean oxygen uptake (VO2), heart rate(HR), and RPE were 1006.33±481.85 ml/min., 133.8±12.5 bpm, and 6.14±0.98A.U., while on the BP protocol, were 684.6±246.3 ml/min., 96.1±10.4 bpm,and 5.08±1.44 A.U., respectively. Significant between-blocks differences were foundfor MPP, RPE, and blood lactate for both exercises. The BS implies higher cardio-respiratory and perceptual demands, though lower power production fluctuation andmovement variability than the BP. The somatic maturation was a strong predictor ofRPA-derived variables in BS. The MPP during all protocol, and the MPP during the BestSet were significant predictable by somatic maturation in both exercises. Mechanical,physiological and perceptual training demands are exercise and maturation dependent.

Bielitzki, R, Behrendt, T, Behrens, M, and Schega, L. Current techniques used for practical blood flow restriction training: a systematic review. J Strength Cond Res 35(10): 2936-2951, 2021-The purpose of this article was to systematically review the available scientific evidence on current methods used for practical blood flow restriction (pBFR) training together with application characteristics as well as advantages and disadvantages of each technique. A literature search was conducted in different databases (PubMed, Web of Science, Scopus, and Cochrane Library) for the period from January 2000 to December 2020. Inclusion criteria for this review were (a) original research involving humans, (b) the use of elastic wraps or nonpneumatic cuffs, and (c) articles written in English. Of 26 studies included and reviewed, 15 were conducted using an acute intervention (11 in the lower body and 4 in the upper body), and 11 were performed with a chronic intervention (8 in the lower body, 1 in the upper body, and 2 in both the upper and the lower body). Three pBFR techniques could be identified: (a) based on the perceptual response (perceived pressure technique), (b) based on the overlap of the cuff (absolute and relative overlap technique), and (c) based on the cuffs' maximal tensile strength (maximal cuff elasticity technique). In conclusion, the perceived pressure technique is simple, valid for the first application, and can be used independently of the cuffs' material properties, but is less reliable within a person over time. The absolute and relative overlap technique as well as the maximal cuff elasticity technique might be applied more reliably due to markings, but require a cuff with constant material properties over time.

Children with obesity tend to have lower level of physical activity compared to non-obese peers. In fact, sedentary behaviors are prevalent in obese children causing difficulties to perform motor tasks and engaging in sport activities. This, in turn, has direct repercussions on adiposity and related comorbidities. The aim of the study was to investigate several components of fitness and their relationship with the degree of fatness in children. We considered 485 Italian schoolchildren (9.5 ± 1.12 years). BMI and prediction modelling outputs of fat mass were employed as markers of body fatness. Physical fitness (PF) was assessed by the 9-item test battery (explosive power, leg muscle power, arm muscle power, upper body power, coordination, agility, speed and endurance). Differences between groups in the PF tests (p &lt, 0.05) were noted. A similar pattern was reflected in both genders. The relationship between anthropometrics’ characteristics and PF tests showed that weight and fat mass had a high level of correlation with different PF tests. Our findings highlight the importance of investigating the degree of fatness in relation with different components of fitness, in children and adolescents. This combination of proxies may cover an unexpectedly helpful screening of the youth population, for both health and performance.

A non-invasive and objective method of capturing upper body surface anatomy, such as 3D optical scanning, would be advantageous for evaluating chest wall deformity. By potentially eliminating the need for computed tomography scanning and superseding manual measurements subject to errors, a system that utilizes optical scanning presents great value to patients and practitioners. This work aimed to quantify the accuracy of two current generation 3D surface scanners, Azure Kinect & StructureIO Mark-II, in assessing the severity of chest wall deformities. 3D surface deviation analysis was conducted on the models created by each scanner, and the findings are reported.

The aim of this study was to analyze the link between the upper and lower body during racewalking. Fifteen male and 16 female racewalkers were recorded in a laboratory as they racewalked at speeds equivalent to their 20-km personal records [men: 1:23:12 (±2:45); women: 1:34:18 (±5:15)]; a single representative trial was chosen from each athlete for analysis and averaged data analyzed. Spatial variables (e.g., stride length) were normalized to stature and referred to as ratios. None of the peak upper body joint angles were associated with speed (p < 0.05) and there were no correlations between pelvic motion and speed, but a medium relationship was observed between peak pelvic external rotation (right pelvis rotated backwards) and stride length ratio (r = 0.37). Greater peak shoulder extension was associated with lower stride frequencies (r = −0.47) and longer swing times (r = 0.41), whereas peak elbow flexion had medium associations with flight time (r = −0.44). Latissimus dorsi was the most active muscle at toe-off during peak shoulder flexion; by contrast, pectoralis major increased in activity just before initial contact, concurrent with peak shoulder extension. Consistent but relatively low rectus abdominis and external oblique activation was present throughout the stride, but increased in preparation for initial contact during late swing. The movements of the pelvic girdle were important for optimizing spatiotemporal variables, showing that this exaggerated movement allows for greater stride lengths. Racewalkers should note however that a larger range of shoulder swing movements was found to be associated with lower stride frequency, and smaller elbow angles with increased flight time, which could be indicative of faster walking but can also lead to visible loss of contact. Coaches should remember that racewalking is an endurance event and development of resistance to fatigue might be more important than strength development.

ObjectiveIntense endurance and strength training mark virtually opposite parts of basic motor skills. Extreme high load physical demands are getting sparer but endurance demands are still present. Therefore, healthy controls and endurance and strength trained athletes at competition level were exposed to a submaximal endurance test of their back muscles.In this pilot study 38 healthy male subjects participated: physically inactive controls (C, n=12), endurance trained (ET, n=13), and strength trained subjects (ST, n=13). All participants were asked to finish a ten minutes back muscle endurance test at 50% of their upper body weight. ResultsMaximum holding times were shortest in the ST group (469±142 s; ET 600±0 s; C 600±0 s), but statistical significance could only be proven for ET vs. ST (p

We sought to determine the vibratory detection thresholds at several points on the upper body that are associated with bony structures. Stimuli were pure tones generated by a voice-coil transducer at eight locations along the spinal column, the clavicle, the sternum and the skull, a point of comparison to past threshold studies. Owing to the transmission properties of mechanical waves in the body, we hypothesized that the detection thresholds would increase with distance from the skull and would depend on frequency in a manner that could reflect the integration of somatosensation and audition.