Concurrent validity and test-retest reliability of the Polhemus Liberty for the measurement of spinal range

This paper discusses concurrent validity and test-retest reliability of the Polhemus Liberty for the measurement of spinal range.It was presented at the International Society of Biomechanics, XXII World Congress, in 2009

Gait and trunk movement patterns of low back pain patients and healthy volunteers during supported and conventional treadmill walking

This study investigates the effects of body weight supported and conventional treadmill walking on gait and trunk motion of asymptomatic people and low back pain (LBP) patients. Forty participants, 19 LBP patients and 21 asymptomatic individuals were recruited. Significant differences were found in gait and trunk kinematic parameters between the two walking conditions, in both participant groups

Analysis of the X-Factor and X-Factor stretch during the completion of a golf practice session in low-handicap golfers

The X-Factor and X-Factor stretch have been positively correlated with golf long game performance. The aim of this study was to compare the X-Factor, X-Factor stretch and long game performance variables pre and following a golf practice session. A group of male golfers (n = 15, handicap = 3.3 ± 1.7) participated in the laboratory-based-study. Movement and performance variables were collected from five golf swings performed pre and following a golf practice session using a motion capture system and launch monitor respectively. Following the practice session, significant increases were observed in the X-Factor (p = 0.00, d = 0.22) and the X-Factor stretch (p = 0.02, d = 0.25). Specifically, the X-Factor increased from 52.82 ± 5.64 ° to 54.06 ± 5.61 ° following the practice session. The X-Factor stretch increased from 1.54 ± 1.05 ° to 1.90 ± 1.41 ° following the practice session. Significant differences were displayed in club head velocity (p = 0.00, d = 0.35), ball velocity (p = 0.01, d = 0.21) and actual carry distance (p = 0.00, d = 0.29) following the practice session. These findings suggest that performing multiple golf shots is not detrimental in terms of muscular fatigue in the long game performance. In actual fact, the findings demonstrate that performing 100 golf shots increases the X-Factor, X-Factor stretch patterns and performance variables which, in turn, increases long game performance. These findings can help PGA golf Professionals improve teaching practices and formulation of golf programmes and warm-up sessions

Biomechanical analysis of lower limbs based on unstable condition sports footwear:a systematic review

The purpose of this paper is to summarize the functional arguments for unstable footwear in the recent research literature and to explore the different effects of various unstable designs of footwear in enhancing muscle strength training, improving stability and loss prevention. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria, to find all the relevant studies for this systematic review, a comprehensive electronic search was conducted. The following keyword combinations were used as part of a standardized electronic literature search strategy: ‘unstable OR bionic OR MBT’ AND ‘shoe OR shoes OR footwear’ AND ‘biomechanics OR kinetics OR kinematics OR muscle force’ from 2000 until November 2021 using the following databases: ScienceDirect, Web of Science and PubMed online. There were 17 articles included in this review, eight consisting of anterior-posterior (AP) unstable condition studies and nine consisting of medial-lateral (ML) unstable condition studies. It was also uncovered that AP unstable footwear is more suitable for fully developed adults, while for ML unstable footwear is perhaps more suitable for children and adolescents

Comparing the activPAL CREA and GHLA algorithms for the classification of postures and activity in free-living children

The activPAL accelerometer has been used extensively in research to assess sedentary behaviour (SB) and physical activity (PA) outcomes. The aim of this study was to assess the comparability of PA and SB outcomes from two automated algorithms (CREA and GHLA) applied to the activPAL accelerometer. One hundred and twenty participants aged 8–12 years wore an activPAL accelerometer on their right thigh continuously for seven days on two occasions, providing valid data from 1058 days. The PALbatch software downloaded the data after applying the CREA and GHLA (latest) algorithms. The comparability of the algorithms were assessed using the mean absolute percent error (MAPE), intra-class correlation coefficients (ICC), and equivalence testing. Comparisons for daily wear time, primary lying, sitting and standing time, sedentary and stepping time, upright time, total number of steps, sit–stand transitions and stepping time ≤ 1 min revealed mainly small MAPE (≤2%), excellent ICCs (lower bound 95% CI ≥ 0.97), and equivalent outcomes. Time spent in sitting bouts > 60 min and stepping bouts > 5 min were not equivalent with the absolute zone needed to reach equivalence (≥7%). Comparable outcomes were provided for wear time and postural outcomes using the CREA or GHLA algorithms, but not for time spent in sitting bouts > 60 min and stepping bouts > 5 min

Electromyographic analyses of the erector spinae muscles during golf swings using four different clubs

The purpose of this study was to compare the electromyography (EMG) patterns of the thoracic and lumbar regions of the erector spinae (ES) muscle during the golf swing whilst using four different golf clubs. Fifteen right-handed male golfers performed a total of twenty swings in random order using the driver, 4-iron, 7-iron and pitching-wedge. Surface EMG was recorded from the lead and trail sides of the thoracic and lumbar regions of the ES muscle (T8, L1 and L5 lateral to the spinous-process). Three-dimensional high-speed video analysis was used to identify the backswing, forward swing, acceleration, early and late follow-through phases of the golf swing. No significant differences in muscle-activation levels from the lead and trail sides of the thoracic and lumbar regions of the ES muscle were displayed between the driver, 4-iron, 7-iron and pitching-wedge (P > 0.05). The highest mean thoracic and lumbar ES muscle-activation levels were displayed in the forward swing (67–99% MVC) and acceleration (83–106% MVC) phases of the swing for all clubs tested. The findings from this study show that there were no significant statistical differences between the driver, 4-iron, 7-iron and pitching-wedge when examining muscle activity from the thoracic and lumbar regions of the ES muscle

The prevalence of lower extremity injuries in running and associated risk factors:a systematic review

Introduction: Running is an extremely popular pastime and competitive sport. There is a general consensus that runners present a high incidence of injury. This study aims to discover the prevalence of injury to the lower extremity among runners and any associated risk factors which correlate with the development of lower extremity injuries. Methods: An inclusion and exclusion criteria were used to screen search results. From an original 184 search results, 24 research papers were selected for the final study. The PRISMA checklist was adhered to in the research process. EndnoteX9 was used to filter through all search results and to achieve the final study selections, in line with the appropriate criteria. Results: Overall, a mean incidence of 37% was displayed for running related injuries to the lower extremity. Females displayed a greater mean incidence of injury than males, 39.7% vs 34.3%. Injury prevalence presented greatest at the knee region (24.3%), but this differed when results were split into male and females. Females presented the greatest prevalence of injury at the calf/lower leg, whilst males presented greatest incidence of injury at the hip/pelvis/upper leg region. Risk factors for developing injury which were identified throughout the research included; having 3 times per week. Conclusion: This systematic review is in agreement with the literature which has repeatedly illustrated that female runners present a greater incidence of injury than male runners

Comparison of thoracic and lumbar erector spinae muscle activation before and after a golf practice session

Lower back pain is commonly associated with golfers. The study aimed: to determine whether thoracic- and lumbar-erector-spinae muscle display signs of muscular fatigue after completing a golf practice session, and to examine the effect of the completed practice session on club head speed, ball speed and absolute carry distance performance variables. Fourteen right-handed male golfers participated in the laboratory-based-study. Surface electromyography (EMG) data was collected from the lead and trail sides of the thoracic- and lumbar-erector-spinae muscle. Normalized root mean squared (RMS) EMG activation levels and performance variables for the golf swings were compared before and after the session. Fatigue was assessed using median frequency (MDF) and RMS during the maximum voluntary contraction (MVC) performed before and after the session. No significant differences were observed in RMS thoracic- and lumbar-erector-spinae muscle activation levels during the five phases of the golf swing and performance variables before and after the session (p > .05). Significant changes were displayed in MDF and RMS in the lead lower lumbar and all trail regions of the erector-spinae muscle when comparing the MVC performed before and after the session (p < .05). Fatigue was evident in the trail side of the erector-spinae muscle after the session

Commercial golf glove effects on golf performance and forearm muscle activity

The study aimed to determine whether or not commercial golf gloves influence performance variables and forearm muscle activity during golf play. Fifteen golfers participated in the laboratory based study, each performing 8 golf swings with a Driver and 7-iron whilst wearing a glove and 8 without wearing the glove. Club head speed, ball speed and absolute carry distance performance variables were calculated. Surface electromyography was recorded from the flexor digitorum superficialis and extensor carpi radialis brevis on both forearm muscles. Club head speed, ball speed and absolute carry distance was significantly higher when using the Driver with the glove in comparison to the Driver without the glove (p < 0.05). No significant differences were evident when using the 7-iron and no significant differences were displayed in muscle activity in either of the conditions. Findings from this study suggest that driving performance is improved when wearing a glove

Intra-session and inter-day reliability of the Myon 320 electromyography system during sub-maximal contractions

Electromyography systems are widely used within the field of scientific and clinical practices. The reliability of these systems are paramount when conducting research. The reliability of Myon 320 Surface Electromyography System is yet to be determined. This study aims to determine the intra-session and inter-day reliability of the Myon 320 Surface Electromyography System. Muscle activity from fifteen participants was measured at the anterior deltoid muscle during a bilateral front raise exercise, the vastus lateralis muscle during a squat exercise and the extensor carpi radialis brevis (ECRB) muscle during an isometric handgrip task. Intra-session and inter-day reliability was calculated by intraclass correlation coefficient, standard error of measurement and coefficient of variation (CV). The normalized root mean squared (RMS) surface electromyographic signals produced good intra-session and inter-day testing intraclass correlation coefficient values (range: 0.63-0.97) together with low standard error of measurement (range: 1.49-2.32) and CV (range: 95% Confidence Interval = 0.36-12.71) measures for the dynamic-and-isometric contractions. The findings indicate that the Myon 320 Surface Electromyography System produces good to fair reliability when examining intra-session and inter-day reliability. Findings of the study provide evidence of the reliability of electromyography between trials which is essential during clinical testing.</p