Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 13 de 13
Filter
Add more filters










Publication year range
1.
Medicine (Baltimore) ; 101(7): e28918, 2022 Feb 18.
Article in English | MEDLINE | ID: mdl-35363215

ABSTRACT

ABSTRACT: Both weightlifting belts and wrist straps are commonly used weightlifting training aids but their effects on deadlift kinematics and performance were still not known. This study examined the effects of weightlifting belts and wrist straps on the kinematics of the deadlift exercise, time to complete a deadlift and rating of perceived exertion (RPE) in male recreational weightlifters.This study used a repeated-measures, within-subjects design. Twenty male healthy recreational weightlifters (mean age ±â€Šstandard deviation = 23.1 ±â€Š2.5 years) were recruited from 2 local gyms and the Education University of Hong Kong between January and April 2021. All participants used various combinations of belt and straps during a conventional deadlift. The hip and knee flexion, cervical lordosis, thoracic kyphosis and lumbar lordosis angles and time to complete a deadlift were measured using video analysis software. RPE was also recorded.Wearing both a belt and wrist straps was found to reduce knee flexion angle (P < .001), but not hip flexion angle (P > .05), during the setup phase of the deadlift compared to wearing no aid. Wearing straps alone exaggerated thoracic kyphosis in the lockout phase of the deadlift compared to wearing a belt alone (P < .001). No changes were seen in cervical and lumbar lordosis angles when using any or both of the weightlifting aids. Additionally, the participants completed deadlifts faster when wearing both a belt and straps (P = .008) and perceived less exertion when wearing a belt and/or straps (P < .001).Weightlifting belts and wrist straps, when using together, have positive effects on the kinematics of deadlift, time to complete a deadlift and RPE in male recreational weightlifters. Trainers should recommend the use of a belt and straps together, but not straps alone, to recreational weightlifters when performing deadlift training.


Subject(s)
Physical Exertion , Wrist , Adult , Biomechanical Phenomena , Exercise , Humans , Male , Weight Lifting , Young Adult
2.
Percept Mot Skills ; 126(3): 389-409, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30803309

ABSTRACT

This randomized controlled trial explored the effects of a Ving Tsun (VT) Chinese martial art training program on reactive standing balance performance, postural muscle reflex contraction latency, leg muscle performance, balance confidence and falls in community-dwelling older adults. We randomly assigned 33 healthy older adults to either a VT group (mean age = 67.5 years) or a control group (mean age = 72.1 years). The VT group received two 1-hour VT training sessions per week for three months (24 sessions). Primary outcome measures collected before and after the intervention period were electromyographic muscle activation onset latencies of the hamstring and gastrocnemius and the center of pressure path, length and movement velocity in standing (reactive balance performance). Secondary outcome measures included isometric peak force and time to isometric peak force of the knee extensors and flexors, the Activities-Specific Balance Confidence Scale score, and fall history. Results revealed that the mean gastrocnemius muscle activation onset latency was significantly longer (22.53 ms) in the VT group after the intervention. The peak force of the knee flexors significantly increased (by 1.58 kg) in the control group over time but not in the VT group. The time to reach peak force in the knee flexors was significantly longer (by 0.51 s) in the control group (but not the VT group) at posttest compared with the pretest value. No other significant group, time, or group-by-time interaction effects were noted. We discussed possible reasons for the failure of three months of martial art training to benefit fall risks among these older adults.


Subject(s)
Accidental Falls/prevention & control , Aging/physiology , Exercise Therapy/methods , Leg/physiology , Martial Arts , Muscle, Skeletal/physiology , Postural Balance/physiology , Aged , Female , Humans , Male , Middle Aged , Treatment Failure
3.
Medicine (Baltimore) ; 98(2): e14134, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30633230

ABSTRACT

In this study, balance performance, agility, eye-hand coordination, and sports performance were compared between amateur badminton players and active controls.Thirty young adult badminton players and 33 active controls participated in the study. Static single-leg standing balance (with eyes closed) was measured using a force platform, and dynamic balance was measured using the Y Balance Test (lower quarter). Agility was measured using a hexagon agility test, and eye-hand coordination was measured using a computerized finger-pointing task. Sports performance was quantified by the number of times a shuttlecock fell in a designated area following a badminton serve.The badminton players had superior accuracy in badminton serving (P < .001) relative to the active controls. However, no significant between-group differences were noted in all other outcome variables (P > .05).Amateur badminton players had more favorable sports performance, but not balance performance, agility, or eye-hand coordination, than controls.


Subject(s)
Athletic Performance/physiology , Movement/physiology , Postural Balance/physiology , Psychomotor Performance/physiology , Racquet Sports/physiology , Adult , Case-Control Studies , Cross-Sectional Studies , Female , Healthy Volunteers , Humans , Male
4.
Gait Posture ; 68: 388-396, 2019 02.
Article in English | MEDLINE | ID: mdl-30590353

ABSTRACT

BACKGROUND: Children with developmental coordination disorder (DCD) have leg muscular deficits which negatively affects their dynamic postural stability. Kinesio tape (KT) could enhance muscle activation, postural control and functional activities in healthy individuals. Therefore, we hypothesized that the usage of KT may address the postural instability problem of children with DCD. RESEARCH QUESTION: To investigate the immediate effect of KT on dynamic postural stability and the associated lower limb muscle activity in children with DCD. METHODS: Forty-nine children with DCD were recruited where twenty-five children were randomly assigned to the KT group (mean age = 8.18 ± 1.16 years) and twenty-four to the control group (mean age = 8.06 ± 0.93 years). KT group received KT application to the rectus femoris and gastrocnemius muscles whereas the control group received no intervention. Measurements were taken before and after the application of KT. Dynamic balance performance was measured using a lower quartile Y-balance test (YBT-LQ). Leg muscle peak activation and time-to-peak muscle activation of the dominant lower limb during YBT-LQ were measured by surface electromyography. RESULTS: YBT-LQ composite score increased by 6.3% in the KT group at posttest (95% CI: -7.308, -2.480). In addition, a higher rectus femoris peak activation was illustrated for YBT-LQ anterior (32.5%; 95% CI: -48.619, -16.395) and posteromedial (24.6%; 95% CI: -42.631, -6.591) reach directions from pretest values in the KT group. Moreover, KT group exhibited a 38% (95% CI: 0.015, 2.983) longer gastrocnemius medialis time-to-peak duration for YBT-LQ posteromedial reach direction when compared to the control group. SIGNIFICANCE: KT revealed an immediate beneficial effect on YBT-LQ performance. Application of KT also increased rectus femoris peak activation and lengthened the muscle time-to-peak duration for specific reach directions. Incorporating KT as an adjunct with dynamic balance training programme could be beneficial for children with DCD.


Subject(s)
Athletic Tape , Lower Extremity/physiopathology , Motor Skills Disorders/therapy , Muscle, Skeletal/physiopathology , Postural Balance/physiology , Child , Electromyography/methods , Female , Humans , Male , Motor Skills Disorders/physiopathology , Muscle Contraction/physiology
5.
Medicine (Baltimore) ; 97(47): e13258, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30461629

ABSTRACT

This study compared the shoulder muscular performance and lean mass between elite and recreational swimmers.Thirty elite swimmers (mean age ±â€Šstandard deviation = 23.1 ±â€Š3.5 years) and 21 recreational swimmers (mean age ±â€Šstandard deviation = 20.8 ±â€Š2.1 years) participated in the study. Maximum muscle strength and time to maximum muscle strength of shoulder flexor, extensor, abductor, and adductor muscles were measured using a handheld dynamometer. Lean mass of the arms and body (excluding the head) were measured using dual-energy x-ray absorptiometry (DXA).Results revealed that compared with recreational swimmers, elite swimmers had higher maximum muscle strength of the shoulder flexor, extensor, abductor, and adductor muscles (all P < .001). The time to reach maximum muscle strength of all shoulder muscles showed no significant difference between the 2 groups (P > .05). The lean mass values in the left arm (P = .037), right arm (P < .001), and whole body (P = .014) were higher in elite swimmers than recreational swimmers.Elite swimmers had greater shoulder maximum muscle strength compared with recreational swimmers though the time taken to reach maximum muscle strength was similar between the 2 groups. Elite swimmers also showed a higher lean mass in both arms and their entire body when compared with recreational swimmers. The results may be useful for recreational swimmers who intend to advance to professional level, and for talent identification and early development of elite swimmers.


Subject(s)
Athletes , Muscle Strength , Muscle, Skeletal , Recreation , Shoulder , Swimming/physiology , Adolescent , Adult , Anthropometry/methods , Athletic Performance/physiology , Female , Humans , Male , Muscle Strength Dynamometer , Muscle, Skeletal/anatomy & histology , Muscle, Skeletal/physiology , Shoulder/anatomy & histology , Shoulder/physiology
6.
Sci Rep ; 8(1): 10330, 2018 07 09.
Article in English | MEDLINE | ID: mdl-29985447

ABSTRACT

This study evaluated the effectiveness of adapted Taekwondo (TKD) training on skeletal development and motor performance in children with developmental coordination disorder (DCD). One hundred forty-five prepubertal children with DCD were allocated to either the TKD or control groups. Children in the TKD group participated in a weekly 1-hour adapted TKD intervention and daily TKD home exercises for 12 weeks. The primary outcome (delay in skeletal development) and secondary outcomes (Movement Assessment Battery for Children (MABC) total impairment score, eye-hand coordination (EHC) scores, and a standing balance score) were measured at baseline, after the intervention and 3 months after the intervention. Skeletal development improved in both groups over time (p < 0.017). The TKD group had a significant delay in skeletal development at baseline compared to the control group (p = 0.003) but caught up with the controls at 3 months (p = 0.041). Improvements in the MABC scores were also seen in both groups across time (p < 0.017). Only the TKD group had a significant improvement in the EHC movement time at 3 (p = 0.009) and 6 months (p = 0.016). The adapted TKD intervention may be effective in improving the skeletal development and EHC movement time of children with DCD. For motor performance, the effect of maturation might be more profound.


Subject(s)
Exercise Therapy , Motor Skills Disorders/therapy , Child , Female , Humans , Male , Martial Arts , Movement , Postural Balance , Treatment Outcome
7.
Gait Posture ; 64: 25-29, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29807269

ABSTRACT

BACKGROUND: Volleyball digging techniques may cause pelvic injuries among female volleyball athletes. Pelvic padding and Kinesiology Taping (KT) may reduce impact force and pain and improve posture during a fall. This study examined the effects of pelvic padding and KT on pain perception, fall kinematics, and kinetics among female volleyball athletes. METHODS: Twenty-four female volleyball athletes were exposed to two pelvic padding scenarios (with and without padding) and two KT conditions (with and without KT applied on the rectus abdominis muscle) during a fall in the forward direction. The maximum impact force during landing and maximum acceleration of the pelvis were registered using a force platform and an accelerometer, respectively. The maximum lumbar (hyper) extension angle, forward reach distance, and total fall time were measured by video analysis. Pain level was quantified using a visual analog scale. RESULTS: The application of pelvic padding (with and without KT) reduced pain when compared to the no padding condition (p < 0.008). Applying KT alone reduced forward reach distance when compared to the 'pelvic padding and KT' condition (p < 0.010). In fact, when both pelvic padding and KT were applied, participants reached further when compared to the 'no pelvic padding and no KT' condition (p < 0.001). No significant main and interaction effects were found in all other outcomes. CONCLUSIONS: Volleyball shorts with pelvic pads are recommended for female volleyball athletes to reduce pain in the digging maneuver and may help to increase their forward reach distance. However, KT is not recommended as it reduces the forward reach distance and cannot reduce pain or improve fall kinematics and kinetics.


Subject(s)
Athletic Injuries/prevention & control , Athletic Tape , Pain Perception/physiology , Pain/physiopathology , Volleyball/physiology , Accelerometry/methods , Accidental Falls , Adolescent , Adult , Athletes , Biomechanical Phenomena , Female , Humans , Kinetics , Pain Measurement , Pelvis , Posture/physiology , Young Adult
8.
Medicine (Baltimore) ; 96(4): e5961, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28121945

ABSTRACT

This cross-sectional exploratory study aimed to quantify and compare the axial and appendicular bone mineral density (BMD), muscle mass, and muscle strength of middle-aged practitioners of Ving Tsun (VT; a hard-style Chinese martial art) with those of nonpractitioners.Eighteen VT practitioners (mean age ±â€Šstandard deviation = 51.8 ±â€Š17.7 years; 12 men and six women) and 36 active controls (mean age ±â€Šstandard deviation = 58.7 ±â€Š11.0 years; 18 men and 18 women) participated in the study. All participants underwent a 1-day battery of musculoskeletal examinations. The BMD of the total radius, total hip, femoral neck, and lumbar spine was measured using dual-energy X-ray absorptiometry, as was the lean mass of the arm, leg, and trunk. Muscle strength of the upper and lower limbs was assessed using a Jamar dynamometer and an isokinetic dynamometer at 60°/second, respectively.VT-trained participants had a 11.5% higher total radius BMD (P = 0.023), a 17.8% higher leg lean mass (P = 0.014), a 56.4% higher isokinetic body weight-adjusted peak torque of the knee extensors (P < 0.001), a 60.8% higher isokinetic body weight-adjusted peak torque of knee flexors (P < 0.001), and a 31.4% shorter time to reach peak torque in the knee flexors (P = 0.001) than the active controls. No significant differences were found in any of the other musculoskeletal outcomes between the 2 groups (P > 0.05).Middle-aged VT practitioners displayed a higher total radius BMD and leg lean mass and better knee extensor and flexor muscular performances than their healthy active counterparts. Healthcare professionals may consider using this alternative method of training to improve the musculoskeletal health of middle-aged adults.


Subject(s)
Martial Arts/physiology , Adult , Aged , Bone Density , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Muscle, Skeletal/physiology
9.
Eur J Sport Sci ; 17(4): 400-406, 2017 May.
Article in English | MEDLINE | ID: mdl-27863454

ABSTRACT

PURPOSE: This study compared the sensory organisation and reactive balance control of amateur rugby players and a control group. METHODS: Forty-one amateur rugby players (22 males: 19 females; mean height ± SD = 168.8 ± 8.8 cm; mean weight ± SD = 63.9 ± 12.5 kg) and 31 control participants (22 males: 9 females; mean height ± SD = 171.5 ± 10.3 cm; mean weight ± SD = 63.8 ± 10.3 kg) completed the study. Their sensory organisation and standing balance performance were evaluated using a sensory organisation test (SOT), and their reactive balance performance was quantified using a motor control test (MCT). The SOT equilibrium scores (ES) and sensory ratios and the MCT motor response latencies were the major outcome measures. RESULTS: The results revealed that compared to the controls, amateur rugby players had lower SOT ESs under different sensory environments (P < .001, [Formula: see text] = 0.142-0.254) and prolonged reactive motor response times in the MCT (P < .001, d = 0.890). The vestibular and visual ratios were also lower in the rugby group (P = .005, [Formula: see text] = 0.107 and 0.108, respectively). No significant difference was found in the somatosensory ratio (P = .853, [Formula: see text] < 0.001) between the two groups. CONCLUSIONS: Amateur rugby players demonstrated inferior standing balance performance compared to their non-trained counterparts. They relied less heavily on vestibular and visual inputs to maintain standing balance under different sensory environments. In addition, they reacted more slowly to postural disturbance, reflecting their suboptimal reactive balance ability in standing.


Subject(s)
Football/physiology , Postural Balance/physiology , Reaction Time/physiology , Adult , Cross-Sectional Studies , Female , Humans , Male , Young Adult
10.
J Sci Med Sport ; 19(11): 946-950, 2016 Nov.
Article in English | MEDLINE | ID: mdl-26996944

ABSTRACT

OBJECTIVES: Postural control strategy and balance performance of rugby players are important yet under-examined issues. This study aimed to examine the differences in balance strategy and balance performance between amateur rugby players and non-players, and to explore training- and injury-related factors that may affect rugby players' balance outcomes. DESIGN: Cross-sectional and exploratory study. METHODS: Forty-five amateur rugby players and 41 healthy active individuals participated in the study. Balance performance and balance strategies were assessed using the sensory organization test (SOT) of the Smart Equitest computerized dynamic posturography machine. Rugby training history and injury history were solicited from the participants. RESULTS: The SOT strategy scores were 1.99-54.90% lower in the rugby group than in the control group (p<0.05), and the equilibrium scores were 1.06-14.29% lower in the rugby group than in the control group (p<0.05). After accounting for age, sex and body mass index, only length of rugby training (in years) was independently associated with the SOT condition 6 strategy score, explaining 15.7% of its variance (p=0.006). There was no association between SOT condition 6 strategy/equilibrium scores and injury history among the rugby players (p>0.05). CONCLUSIONS: Amateur rugby players demonstrated inferior balance strategy and balance performance compared to their non-training counterparts. Their suboptimal balance strategy was associated with insufficient training experience but not with history of injury.


Subject(s)
Athletic Performance/physiology , Football/physiology , Postural Balance/physiology , Adult , Case-Control Studies , Cross-Sectional Studies , Female , Humans , Male , Time Factors , Young Adult
11.
Motor Control ; 18(2): 103-11, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24018555

ABSTRACT

This study compared the sensory organization and standing balance of adolescent tennis players, taekwondo (TKD) practitioners, and healthy control participants. Sixty participants including 12 tennis players, 21 TKD practitioners, and 27 healthy control participants were tested. All of the participants underwent the Sensory Organization Test (SOT) and the Unilateral Stance Test (UST) on a Smart Equitest system. Results revealed that tennis players had higher SOT visual ratios than the control participants (p = .005), and TKD practitioners swayed more slowly in the UST than the control participants (p = .039). No differences (p > .05) were found in the composite score, somatosensory ratio, or vestibular ratio between the groups. Tennis players swayed less when they relied more on visual input to maintain balance, whereas TKD practitioners were more stable when standing on one leg. Parents may consider these sports as recreational activities for their children to develop specific balance abilities.


Subject(s)
Martial Arts/physiology , Postural Balance/physiology , Sensation/physiology , Tennis/physiology , Vestibule, Labyrinth/physiology , Visual Perception/physiology , Adolescent , Analysis of Variance , Body Height , Body Weight , Case-Control Studies , Child , Cross-Sectional Studies , Female , Humans , Male
12.
Integr Cancer Ther ; 13(1): 54-61, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23749481

ABSTRACT

HYPOTHESIS: Qigong exercise is a popular method for relieving the side effects of conventional cancer treatments in survivors of breast cancer, yet its effects are not empirically assessed. This study aimed to investigate the effects of qigong exercise on upper limb lymphedema, arterial resistance, and blood flow velocity in survivors with breast cancer and mastectomy. STUDY DESIGN: This study was conducted as a prospective clinical trial. METHODS: Eleven survivors of breast cancer with qigong experience (mean age = 58.3 ± 10.1 years) were assigned to the experimental group and 12 survivors of breast cancer without qigong experience (mean age = 53.8 ± 4.2 years) were assigned to the control group. They all had breast cancer-related lymphedema. All procedures were completed within one session. After baseline measurements were taken, the experimental group performed 18 Forms Tai Chi Internal Qigong for approximately 6 minutes while the control group rested for similar duration in a sitting position. Both groups were then reassessed. All participants were measured on their affected upper limb circumference (by using tape measures), peripheral arterial resistance, and blood flow velocities (using a Doppler ultrasound machine). RESULTS: The between-group differences were not significant for all outcome measures at baseline (P > .05). The circumferences of the affected upper arm, elbow, forearm and wrist decreased after qigong exercise (P < .05). However, no significant difference was found in the circumference measures between the 2 groups posttest (P > .0125). In terms of vascular outcomes, the resistance index decreased and the maximum systolic arterial blood flow velocity (SV) and minimum diastolic arterial blood flow velocity (DV) increased significantly after qigong exercise (P < .05). The between-group difference was close to significant for SV (P = .018) and was significant for DV (P < .001) posttest. CONCLUSION: Qigong exercise could reduce conventional cancer therapy side effects such as upper limb lymphedema and poor circulatory status in survivors of breast cancer. However, such effects may be temporary, and further studies must be conducted to explore longer term effects.


Subject(s)
Breast Neoplasms , Lymphedema/prevention & control , Qigong , Survivors , Upper Extremity/blood supply , Aged , Breast Neoplasms/mortality , Breast Neoplasms/rehabilitation , Exercise/physiology , Female , Humans , Lymphedema/epidemiology , Middle Aged , Pilot Projects , Qigong/methods , Quality of Life , Regional Blood Flow , Tai Ji , Treatment Outcome
13.
Res Dev Disabil ; 34(5): 1446-55, 2013 May.
Article in English | MEDLINE | ID: mdl-23474997

ABSTRACT

This randomized controlled trial aimed to investigate the effect of short-term intensive TKD training on the isokinetic knee muscle strength and reactive and static balance control of children with developmental coordination disorder (DCD). Among the 44 children with DCD (mean age: 7.6 ± 1.3 years) recruited, 21 were randomly assigned to undergo daily TKD training for 1h over three consecutive months, with the remaining 23 children being assigned to the DCD control group. Eighteen typically developing children (mean age: 7.2 ± 1.0 years) received no training as normal controls. Knee extensor and flexor muscle strength and reactive and static balance control were assessed using an isokinetic machine (with low, moderate and high movement velocities), a motor control test (MCT) and a unilateral stance test (UST), respectively. A repeated measures MANCOVA revealed a significant group through time interaction effect in isokinetic outcomes at 180°/s and in the UST outcome. Post hoc analysis demonstrated that DCD-TKD children's isokinetic knee muscle strength, specifically at 180°/s, was as high as that of the normal control children (p>0.0083) after TKD training. Moreover, UST body sway velocity was slower in the DCD-TKD group than in the DCD control group (p<0.001), and was comparable to that of the normal control group (p>0.05) after TKD training. However, no such improvement in balance was observed in the MCT (p>0.025). The results show that children with DCD who undergo a 3-month program of intensive TKD training experience improvements in isokinetic knee muscle strength at 180°/s and static single-leg standing balance control, but do not benefit from improved reactive balance control.


Subject(s)
Exercise Therapy/methods , Knee Joint/physiology , Martial Arts , Motor Skills Disorders/therapy , Muscle Strength/physiology , Postural Balance/physiology , Child , Female , Humans , Male , Motor Skills/physiology , Motor Skills Disorders/physiopathology , Quadriceps Muscle/physiology , Single-Blind Method , Torque , Treatment Outcome
SELECTION OF CITATIONS
SEARCH DETAIL
...