The 2010 regulations on golf groove design: impact on ball flight characteristics during a controlled shot.

The purpose of this study was to investigate the difference in the amount of spin that can be generated during a controlled golf shot, as a result of the 2010 rule change regarding restrictions applied to the design of the grooves on the clubface implemented by the United States Golf Association and the Royal & Ancient Golf Club. Ten experienced golfers (mean ± SD; age, 23.0 ± 0.67 yr; playing experience, 13.2 ± 1.6 yr; handicap, 1.6 ± 1.4) were required to play a total of 120 shots inside a state of the art golf simulator with 3 clubs consisting of ‘old’ pre 2010 U-groove design and ‘new’ post 2010 V-groove design. With the U and V grooved clubs, participants played 10 shots from a fairway mat and 10 shots from a rough mat using a 9 iron, PW and SW. Backspin (RPM) and, as a measure of accuracy, distance landed from the pin (yds) were recorded. Compared to the U-grooves, the newer V-groove design imparted significantly less backspin from both the fairway and rough surfaces (P < 0.05), additionally, shots with all clubs were consistently further away from the pin (P < 0.05). The newer groove design does not enable players to impart as much backspin on the ball as they previously could and our data suggest that the recent change in golf club design might therefore reward driving accuracy

Analyzing Thoracic Spine and Hip Mobility and the Effects on Kinematics in the Golf Swing and its Relation to Injury and Performance

Analyzing Thoracic Spine and Hip Mobility and the Effects on Kinematics in the Golf Swing and its Relation to Injury and Performance Abstract Low back pain (LBP) and low back injury have been found to be the most common symptom and injury sustained while playing golf (McHardy et al., 2006). Previous research has sought to determine precursors to injury by investigating physical limitations including hip internal rotation deficits. This study aims to build upon previous research by measuring joint mobility and forces placed on the lower back during the golf swing. Specifically, it evaluates active range of motion of both thoracic and hip rotation as well as joint kinematics and moment stressed placed on the low back during the golf swing. To test the hypothesis that limited range of motion leads to higher levels of stress placed on the low back, subjects were assessed using movement screens created by the Titleist Performance Institute. Following the completion of tests, participants were placed into a “Healthy” or “Limited Mobility” group. All subjects hit 10 golf balls with their driver, with five trials being used for analysis based on carry distance calculated by FlightScope Mevo. Joint kinematics were compared using a Two-Factor Mixed Design ANOVA and low back moments were analyzed using a One-Sided Independent T-Test. No significant differences were found when comparing joint kinematics across both groups. Additionally, no significant differences were found when comparing low back moment across both groups. These results suggest that physical limitations do not necessarily lead to higher forces to be experienced by the low back. With this in mind, further research should be done to analyze potential causative factors of low back pain in golfers, specifically, swing characteristics and volume of practice and play

A Golf Programme for People with Severe and Enduring Mental Health Problems

This article reports a pioneering golf programme for people with severe and enduring mental health problems. Following a discussion of the problems and possibilities of golf as a form of physical activity for this group, we outline the structure, organisation, and ethos of the golf programme. Through an analysis of qualitative case study data collected during the programme, we discuss the response to the programme from service users and mental health professionals. We conclude by highlighting aspects of the programme which were critical to its success and offering suggestions for further initiatives in this area

A Statistical Analysis of 10-pin Bowling Scores and an Examination of the Fairness of Alternative Handicapping Systems

Using data on approximately 1240 games of bowling we examine the statistical properties of 10-pin bowling scores. We find evidence that that the distribution of bowling scores is approximately log-normally distributed with a common variance across players. This allows us to consider the effectiveness of alternative handicapping systems in allowing less skilled bowlers to compete against more skilled opponents. We show that the current system mitigates against bowlers of low skill and propose a new system which we show works well in equalising the playing field across all match-ups.

Understanding the effect of seams on the aerodynamics of an association football

The aerodynamic properties of an association football were measured using a wind tunnel arrangement. A third scale model of a generic football (with seams) was used in addition to a 'mini-football'. As the wind speed was increased, the drag coefficient decreased from 0.5 to 0.2, suggesting a transition from laminar to turbulent behaviour in the boundary layer. For spinning footballs, the Magnus effect was observed and it was found that reverse Magnus effects were possible at low Reynolds numbers. Measurements on spinning smooth spheres found that laminar behaviour led to a high drag coefficient for a large range of Reynolds numbers, and Magnus effects were inconsistent, but generally showed reverse Magnus behaviour at high Reynolds number and spin parameter. Trajectory simulations of free kicks demonstrated that a football that is struck in the centre will follow a near straight trajectory, dipping slightly before reaching the goal, whereas a football that is struck off centre will bend before reaching the goal, but will have a significantly longer flight time. The curving kick simulation was repeated for a smooth ball, which resulted in a longer flight time, due to increased drag, and the ball curving in the opposite direction, due to reverse Magnus effects. The presence of seams was found to encourage turbulent behaviour, resulting in reduced drag and more predictable Magnus behaviour for a conventional football, compared with a smooth ball. © IMechE 2005