Rizal Razman

Dr. Rizal Razman

University of Malaya
orcid

Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 February 2021 in Sensors
Verified
Journal Article
Open access
PDF file
FFFranz Konstantin Fuss
Franz Konstantin Fuss
Asliza AhmadAsliza Ahmad
Asliza Ahmad
ATAdin Tan
Adin Tan
RRRizal Razman
Rizal Razman
Yehuda WeizmanYehuda Weizman
Yehuda Weizman
Hard-shell thoracolumbar sacral orthoses (TLSOs) are used for treating idiopathic scoliosis, a deformation of the spine with a sideways curvature. The pressure required inside the TLSO for ideal corrective results remains unclear. Retrofitting TLSOs with commercially available pressure measurement systems is expensive and can only be performed in a laboratory. The aim of this study was to develop a cost-effective but accurate pressure sensor system for TLSOs. The sensor was built from a piezoresistive polymer, placed between two closed-cell foam liners, and evaluated with a material testing machine. Because foams are energy absorbers, the pressure-conductance curve was affected by hysteresis. The sensor was calibrated on a force plate with the transitions from loading to unloading used to establish the calibration curve. The root mean square error was 12% on average within the required pressure range of 0.01–0.13 MPa. The sensor reacted to the changing pressure during breathing and different activities when tested underneath a chest belt at different tensions. The peak pressure reached 0.135 MPa. The sensor was further tested inside the scoliosis brace during different activities. The measured pressure was 0.014–0.124 MPa. The results from this study enable cheaper and mobile systems to be used for clinical studies on the comfort and pressure of braces during daily activities.

21 August 2023 in Applied Sciences
Verified
Journal Article
Open access
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YRYuvaraj Ramasamy
Yuvaraj Ramasamy
JUJuliana Usman
Juliana Usman
RRRizal Razman
Rizal Razman
Ming Wei YeapMing Wei Yeap
Ming Wei Yeap
HTHarley Towler
Harley Towler
Mark KingMark King
Mark King
The shoulder is a unique and complex joint in the human body with three bones and four joints, which makes it the most unstable joint in the body due to the amount of motion. To improve approaches toward understanding the performance of overhead throwing movements, this systematic review summarizes the type of analysis related to shoulder biomechanics involving overhead sporting motions. A search of seven databases identified 33 eligible studies, which were subsequently scored using the Modified Coleman Methodology Score scale. A total of nine articles from badminton, seven from baseball, five from volleyball, five from tennis, three from cricket, and one from softball were reviewed. All 33 studies evaluated shoulder kinematics and 12 of them also investigated the forces and torques (kinetics). The most common methods used were 3D motion analysis (76%), digital video cameras (15%), electromagnetic tracking system (6%), and finally 3% used IMU sensors. Overall, shoulder external rotation during the back swing, internal rotation, and elbow extension during the forward acceleration phase were the strongest predictors of high velocity overhead throwing movement. The findings provide some useful insights and guidance to researchers in their future contribution to the existing body of literature on shoulder overhead throwing movement biomechanics.

7 May 2020 in Disability & Society
Verified
Journal Article
Closed access
JCJadeera P.G Cheong
Jadeera P.G Cheong
SKSelina Khoo
Selina Khoo
CIChiaki Inoue
Chiaki Inoue
JSJhalukpreya Surujlal
Jhalukpreya Surujlal
NCNiki Cheong
Niki Cheong
RRRizal Razman
Rizal Razman
The Paralympic Games is the largest sporting competition for athletes with an impairment. This competition has, however, had limited news coverage in the past particularly compared to the Olympic Games. This study analyzes newspaper coverage of the 2016 Paralympic Games by two newspapers in 11 countries (China, Iran, Japan, Malaysia, Oman, Saudi Arabia, Singapore, South Africa, South Korea, Taiwan, and the United Kingdom). The coverage period spanned 7-19 September 2016. Text and pictures were coded according to page number, content, gender, sport, and nationality of person. Media content analysis was used to extract coverage of themes. Results are presented using descriptive statistics and frequency counts. Of the 623 articles and 541 photographs analysed, a small percentage (7.3%) were on the front pages of newspapers. Most articles and photographs (78.7%) were about athletes or teams. There was more coverage of male athletes (53.2%) and local athletes (71.6%).

29 September 2022 in Journal of Intellectual Disabilities
Verified
Journal Article
Closed access
YHYaru Hao
Yaru Hao
RRRizal Razman
Rizal Razman
This systematic review aimed to explore the influence of family factors on physical activity in children with intellectual disability. How and what family factors that specifically influence physical activity has not been compiled and reviewed previously. In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic search was performed for articles published in English and Chinese without any year limits in six databases. Ten studies met the eligibility criteria and were included in the review. All studies were qualitatively integrated to identify and compare positive and negative family factors. A total of 1135 participants, of which 497 were children with intellectual disability while the other 638 participants were family members (parents, siblings and caregivers). The family factors of 6 themes and 18 sub-themes (10 positive, 7 negative and 1 inconclusive factors) were extracted. Overall, these results highlight the importance of encouragement, support and involvement by family members, concurrently it points out that parental psychological factors, socioeconomic status, responsibilities and electronic devices could both promote and hinder engagement in physical activity for children with intellectual disability. The findings accentuate the role of the family unit in helping determine the activity levels of children with intellectual disability. Future studies should include a wider range of participants and be longitudinal in nature, utilizing more accurate monitoring tools.

15 January 2022 in Applied Sciences
Verified
Journal Article
Open access
PDF file
YRYuvaraj Ramasamy
Yuvaraj Ramasamy
VSVISWANATH SUNDAR
VISWANATH SUNDAR
JUJuliana Usman
Juliana Usman
RRRizal Razman
Rizal Razman
HTHarley Towler
Harley Towler
Mark KingMark King
Mark King
Three-dimensional position data of nineteen elite male Malaysian badminton players performing a series of maximal jump smashes were collected using a motion capture system. A ‘resultant moments’ inverse dynamics analysis was performed on the racket arm joints (shoulder, elbow and wrist). Relationships between racket head speed and peak joint moments were quantified using correlational analyses, inclusive of a Benjamini–Hochberg correction for multiple-hypothesis testing. The racket head centre speed at racket–shuttlecock contact was, on average, 61.2 m/s with a peak of 68.5 m/s which equated to average shuttlecock speeds of 95.2 m/s with a peak of 105.0 m/s. The correlational analysis revealed that a larger shoulder internal rotation moment (r = 0.737), backwards shoulder plane of elevation moment (r = 0.614) and wrist extension moment (r = −0.564) were associated with greater racket head centre speed at racket–shuttlecock contact. Coaches should consider strengthening the musculature associated with shoulder internal rotation, plane of elevation and wrist extension. This work provides a unique analysis of the joint moments of the racket arm during the badminton jump smash performed by an elite population and highlights significant relationships between racket head speed and peak resultant joint moments.

17 January 2023 in PLOS ONE
Verified
Journal Article
Open access
PDF file
NZNureen Zaghlul
Nureen Zaghlul
SGSiew Li Goh
Siew Li Goh
RRRizal Razman
Rizal Razman
MAHMOUD DANAEEMAHMOUD DANAEE
MAHMOUD DANAEE
CCCHOW KHUEN CHAN
CHOW KHUEN CHAN
The validity and reliability of the Lafayette stability platform are well-established for double leg testing. However, no evaluation of single leg (SL) stance on the platform was discovered yet. Therefore, this study aimed to investigate the reliability of conducting the SL stance on the Lafayette platform. Thirty-six healthy and active university students (age 23.2 ± 3.2 years; BMI 21.1 ± 3.1 kg/m2) were tested twice, one week apart (week 1; W1, week 2; W2). They stood on their dominant leg with eyes-open (EO) and eyes-closed (EC) in random order. Three successful trials of 20 seconds each were recorded. The duration during which the platform was maintained within 0° of tilt was referred to as time in balance (TIB). At all-time points, TIB was consistently longer in EO (EOW1: 17.02 ± 1.04s; EOW2: 17.32 ± 1.03s) compared to EC (ECW1: 11.55 ± 1.73s; ECW2: 13.08 ± 1.82s). A ±10 seconds difference was demonstrated in the Bland-Altman analysis in both EO and EC. Lower standard error of measurement (SEM) and coefficient of variation (CV) indicated consistent output. High intraclass correlation coefficient (ICC) values were seen between weeks (EO = 0.74; EC = 0.76) and within weeks (EOW1 = 0.79; EOW2 = 0.86; ECW1 = 0.71; ECW2 = 0.71). Although statistical measures (i.e., SEM, CV, and ICC) indicated good reliability of Lafayette for SL tasks, the wide agreement interval is yet to be clinically meaningful. Factors underlying the wide variation need to be identified before Lafayette is used for TIB assessment.