Research Paper

Fatigue injury risk in anterior cruciate ligament of target side knee during golf swing

Abstract: Publication date: Available online 14 December 2016 Source:Journal of Biomechanics Author(s): Tserenchimed Purevsuren, Moon Seok Kwon, Won Man Park, Kyungsoo Kim, Seung Ho Jang, Young-Tae Lim, Yoon Hyuk Kim A golf-related ACL injury can be linked with excessive golf play or practice because such over-use by repetitive golf swing motions can increase damage accumulation to the ACL bundles. In this study, joint angular rotations, forces, and moments, as well as the forces and strains on the ACL of the target-side knee joint, were investigated for ten professional golfers using the multi-body lower extremity model. The fatigue life of the ACL was also predicted by assuming the estimated ACL force as a cyclic load. The ACL force and strain reached their maximum values within a short time just after ball-impact in the follow-through phase. The smaller knee flexion, higher internal tibial rotation, increase of the joint compressive force and knee abduction moment in the follow-through phase were shown as to lead an increased ACL loading. The number of cycles to fatigue failure (fatigue life) in the ACL might be several thousands. It is suggested that the excessive training or practice of swing motion without enough rest may be one of factors to lead to damage or injury in the ACL by the fatigue failure. The present technology can provide fundamental information to understand and prevent the ACL injury for golf players.

Pub.: 21 Dec '16, Pinned: 10 Jan '17

Research Paper

Return to Golf After Lumbar Fusion.

Abstract: Spinal fusion surgery is being increasingly performed, yet few studies have focused on return to recreational sports after lumbar fusion and none have specifically analyzed return to golf.Most golfers successfully return to sport after lumbar fusion surgery.Case series.Level 4.All patients who underwent 1- or 2-level primary lumbar fusion surgery for degenerative pathologies performed by a single surgeon between January 2008 and October 2012 and had at least 1-year follow-up were included. Patients completed a specifically designed golf survey. Surveys were mailed, given during follow-up clinic, or answered during telephone contact.A total of 353 patients met the inclusion and exclusion criteria, with 200 responses (57%) to the questionnaire producing 34 golfers. The average age of golfers was 57 years (range, 32-79 years). In 79% of golfers, preoperative back and/or leg pain significantly affected their ability to play golf. Within 1 year from surgery, 65% of patients returned to practice and 52% returned to course play. Only 29% of patients stated that continued back/leg pain limited their play. Twenty-five patients (77%) were able to play the same amount of golf or more than before fusion surgery. Of those providing handicaps, 12 (80%) reported the same or an improved handicap.More than 50% of golfers return to on-course play within 1 year of lumbar fusion surgery. The majority of golfers can return to preoperative levels in terms of performance (handicap) and frequency of play.This investigation offers insight into when golfers return to sport after lumbar fusion surgery and provides surgeons with information to set realistic expectations postoperatively.

Pub.: 24 Nov '16, Pinned: 24 Nov '16

Research Paper

How to quantify the transition phase during golf swing performance: Torsional load affects low back complaints during the transition phase.

Abstract: The transition phase of a golf swing is considered to be a decisive instant required for a powerful swing. However, at the same time, the low back torsional loads during this phase can have a considerable effect on golf-related low back pain (LBP). Previous efforts to quantify the transition phase were hampered by problems with accuracy due to methodological limitations. In this study, vector-coding technique (VCT) method was proposed as a comprehensive methodology to quantify the precise transition phase and examine low back torsional load. Towards this end, transition phases were assessed using three different methods (VCT, lead hand speed and X-factor stretch) and compared; then, low back torsional load during the transition phase was examined. As a result, the importance of accurate transition phase quantification has been documented. The largest torsional loads were observed in healthy professional golfers (10.23 ± 1.69 N · kg(-1)), followed by professional golfers with a history of LBP (7.93 ± 1.79 N · kg(-1)), healthy amateur golfers (1.79 ± 1.05 N · kg(-1)) and amateur golfers with a history of LBP (0.99 ± 0.87 N · kg(-1)), which order was equal to that of the transition phase magnitudes of each group. These results indicate the relationship between the transition phase and LBP history and the dependency of the torsional load magnitude on the transition phase.

Pub.: 18 Nov '16, Pinned: 18 Nov '16

Research Paper

Comparison of centre of gravity and centre of pressure patterns in the golf swing.

Abstract: Analysing the centre of pressure (COP) and centre of gravity (COG) could reveal stabilising strategies used by golfers throughout the golf swing. This study identified and compared golfers' COP and COG patterns throughout the golf swing in medial-lateral (ML) and anterior-posterior (AP) directions using principal component analysis (PCA) and examined their relationship to clubhead velocity. Three-dimensional marker trajectories were collected using Vicon motion analysis and force plate data from two Kistler force plates for 22 low-handicap golfers during drives. Golfers' COG and COP were expressed as a percentage distance between their feet. PCA was performed on COG and COP in ML and AP directions. Relationships between principal component (PC) scores were examined using Pearson correlation and regression analysis used to examine the relationship with clubhead velocity. ML COP movements varied in magnitude (PC1), rate of change and timing (PC2 and PC3). The COP and COG PC1 scores were strongly correlated in both directions (ML: r = 0.90, P < .05; AP: r = 0.81, P < .05). Clubhead velocity, explained by three PCs (74%), related to timing and rate of change in COPML near downswing (PC2 and PC3) and timing of COGML late backswing (PC2). The relationship between COPML and COGML PC1 scores identified extremes of COP and COG patterns in golfers and could indicate a golfer's dynamic balance. Golfers with earlier movement of COP to the front foot (PC2) and rate of change (PC3) patterns in ML COP, prior to the downswing, may be more likely to generate higher clubhead velocity.

Pub.: 16 Oct '16, Pinned: 17 Oct '16

Research Paper

Vibration characteristics of golf club heads in their handheld grinding process and potential approaches for reducing the vibration exposure

Abstract: To control vibration-induced white finger among workers performing the fine grinding of golf club heads, the aims of this study are to clarify the major vibration sources in the grinding process, to identify and understand the basic characteristics of the club head vibration, and to propose potential approaches for reducing the vibration exposure. The vibrations on two typical club heads and two belt grinding machines were measured at a workplace. A simulated test station was also constructed and used to help examine some influencing factors of the club head vibration. This study found that the club head vibration was the combination of the vibration transmitted from the grinding machines and that generated in the grinding process. As a result, any factor that affects the machine vibration, the grinding vibration, and/or the dynamic response of the club head can influence the vibration exposure of the fingers or hands holding the club head in the grinding process. The significant influencing factors identified in the study include testing subject, grinding machine, machine operation speed, drive wheel condition, club head model, mechanical constraints imposed on the club head during the grinding, and machine foot pad. These findings suggest that the vibration exposure can be controlled by reducing the grinding machine vibration, changing the workpiece dynamic properties, and mitigating the vibration transmission in its pathway. Many potential methods for the control are proposed and discussed.

Pub.: 23 Sep '16, Pinned: 12 Oct '16

Research Paper

The relationships between golf and health: a scoping review.

Abstract: To assess the relationships between golf and health.Scoping review.Published and unpublished reports of any age or language, identified by searching electronic databases, platforms, reference lists, websites and from consulting experts.A 3-step search strategy identified relevant published primary and secondary studies as well as grey literature. Identified studies were screened for final inclusion. Data were extracted using a standardised tool, to form (1) a descriptive analysis and (2) a thematic summary.4944 records were identified with an initial search. 301 studies met criteria for the scoping review. Golf can provide moderate intensity physical activity and is associated with physical health benefits that include improved cardiovascular, respiratory and metabolic profiles, and improved wellness. There is limited evidence related to golf and mental health. The incidence of golfing injury is moderate, with back injuries the most frequent. Accidental head injuries are rare, but can have serious consequences.Practitioners and policymakers can be encouraged to support more people to play golf, due to associated improved physical health and mental well-being, and a potential contribution to increased life expectancy. Injuries and illnesses associated with golf have been identified, and risk reduction strategies are warranted. Further research priorities include systematic reviews to further explore the cause and effect nature of the relationships described. Research characterising golf's contribution to muscular strengthening, balance and falls prevention as well as further assessing the associations and effects between golf and mental health are also indicated.

Pub.: 05 Oct '16, Pinned: 11 Oct '16

Research Paper

A randomized trial of traditional and golf-specific resistance training in amateur female golfers: Benefits beyond golf performance.

Abstract: Compare golf-specific resistance training (GSRT) with traditional resistance training (TRAD) with regard to golf performance and other outcome measures.Randomized controlled study.Outpatient gym.45 female golfers were randomized into TRAD or GSRT, both of which targeted muscles active during the golf swing. Participants performed supervised training 3d(.)wk(-1) for 10 weeks.Golf performance, bone density, body composition, and physical performance tests.29 individuals (58.1 ± 2.1y; 15 TRAD, 14 GSRT) completed training. Completers were older (p = 0.048) and played golf more frequently than non-completers (p = 0.002), but were not otherwise different. Training decreased whole body fat mass (p = 0.013) and visceral fat mass (p = 0.033) across groups, but did not influence lean mass (p = 0.283) or bone mineral density (p = 0.205). Training increased driver speed (p = 0.001), driver distance (p = 0.020), and 7I distance (p < 0.001), but not 7I speed (p = 0.160), but no group or interaction effects were present. Training increased all physical performance tests (p ≤ 0.005) regardless of group, but the seated medicine ball throw was most related to baseline driver speed (r(2) = 0.384), and also most responsive to training (r(2) = 0.250).10 weeks of supervised TRAD and GSRT provided similar improvements in body composition, golf performance, and physical performance in amateur female golfers.

Pub.: 02 Sep '16, Pinned: 02 Sep '16

Research Paper

Predicting golf ball trajectories from swing plane: An artificial neural networks approach

Abstract: Quantifying and validating descriptive heuristic rules that govern someone's skills and expertise have been known philosophical quest since the early Greek philosophers. Inherent to sport coaching is the qualitative assessment of complex human motion patterns, relying on subjective and ‘hard-to-quantify’ criteria that can be subject to experts/coaches disagreement. This paper presents an application of Artificial Neural Networks (ANN) for the discovery of predictive power of swing plane heuristic rules influencing golf ball trajectories. A golf data set (531 samples from 14 golfers) utilised in the experiments, was captured via ubiquitous computing device embedded in the handle of a driver club. Out of multiple swing performance factors influencing the ball trajectory, the selected subset of features for subspace modelling was linked only to the swing plane concept. Quantitative evidence supporting empirical coaching rules for swing plane assessment were obtained by supervised learning of ANN models. Optimised ANN models Radial Basis Function (RBF) and Support Vector Machine (SVM), were able to draw inference from captured swing data linking ball trajectories with variations of swing plane (with overall classification of 87%). The obtained swing plane computer model inference, data analysis and implemented concept of generic data export utility support kinesiology, golf coaching, inform club fitting, golf manufacturing technology and demonstrate new cross- and multi-disciplinary integration of sport science, augmented coaching, ubiquitous computing, computational intelligence and the applications of expert systems for growing availability of sport, injury prevention/rehabilitation and golf related data sets.

Pub.: 14 Jul '16, Pinned: 22 Jul '16

Research Paper

Effect of Clubhead Inertial Properties and Driver Face Geometry on Golf ball Trajectories ☆

Abstract: There are many factors that influence the amount of side-spin imparted to a golf ball during impact with a driver. In general, the best golf drives are launched with minimal side-spin, producing a straight ball trajectory with maximum carry distance. During off-centre impacts, side-spin is generated due to a phenomenon known as the “gear effect.” The extent of the gear effect depends on clubhead design parameters such as the moment of inertia and centre of gravity location. The bulge of a driver is a design feature implemented to counter-act the side-spin produced by the gear effect. In this investigation, an impulse-momentum impact model and an aerodynamic ball flight model are used to (i) examine the effect of the centre of gravity depth (distance from clubface) on ball trajectory during off-centre impacts, (ii) test the efficacy of movable weight technology, and (iii) optimize the bulge radius in relation to the clubhead's centre of gravity depth and moment of inertia. In the first study, it is qualitatively shown that side-spin increases linearly with increasing centre of gravity depth. In the second study, it is found that movable weights can have a significant effect on ball trajectory, especially at higher swing speeds. In the third study, a relationship between the bulge radius, centre of gravity depth, and moment of inertia is developed, and an equation for calculating the optimum bulge radius is fit to the simulation results.

Pub.: 09 Jul '16, Pinned: 14 Jul '16

Research Paper

Biomechanical Evaluation of Dynamic Balance Control Ability During Golf Swing

Abstract: Balance ability seems to be significantly correlated with golfing skill. However, it is unclear whether dynamic balance control has a direct influence on golf swing performance. In this study, the effects of a golfer’s skill level on the observed dynamic balance control ability during the golf swing were evaluated. Fifty participants were divided into three groups (professional, advanced, and novice) based on their official handicap scores. Six infrared cameras and two force platforms were used to determine dynamic alterations of the center of mass (COM) and center of pressure (COP). The peak-to-peak displacement and velocity of the COM and COP in the professional golfers were generally lower than those of the other golfers. However, the professional golfers displayed significantly greater COM displacement than that of the advanced amateur golfers in the lead/trail direction (p < 0.01). This does not directly imply deterioration of the dynamic balance ability since the COM-COP separation decreased as the skill level of the golfers increased. The professional golfers had superior dynamic balance ability, achieved by controlling the COP excursion to compensate for the increased variation of COM, leading to a more stable swing mechanism than that of the amateur golfers. This study provides quantitative information for the evaluation of dynamic balance control during the golf swing.

Pub.: 06 Jun '16, Pinned: 14 Jul '16

Research Paper

A novel method to grip a golf club for a quadruple amputee golfer

Abstract: A device was created to enable a quadruple amputee golfer to securely hold a golf club and play the game. The device also offers a way to easily and independently switch one golf club for another during the round. It comprises a spring-loaded cylindrical fixture to hold the club to the prosthetic arm and a J-slot to twist and release the club to exchange it for a different club on the course. The device has been used to play golf for 5 years. The engineered solution attaches to the golfer’s right arm and he swings using a right-handed stance. It includes a bend in the prosthetic arm to enable a more functional golf swing. A series of club fittings were conducted over a number of years and experiments were conducted on both driving ranges and golf courses with the aim of optimizing performance. The complete set of club specifications is included along with typical shot results for selected clubs. A device was created to enable a quadruple amputee golfer to securely hold a golf club and play the game. The device also offers a way to easily and independently switch one golf club for another during the round. It comprises a spring-loaded cylindrical fixture to hold the club to the prosthetic arm and a J-slot to twist and release the club to exchange it for a different club on the course. The device has been used to play golf for 5 years. The engineered solution attaches to the golfer’s right arm and he swings using a right-handed stance. It includes a bend in the prosthetic arm to enable a more functional golf swing. A series of club fittings were conducted over a number of years and experiments were conducted on both driving ranges and golf courses with the aim of optimizing performance. The complete set of club specifications is included along with typical shot results for selected clubs.

Pub.: 01 Sep '16, Pinned: 15 Aug '16