Effect of moment of inertia and physical profile on restricted motion swing speed

The maximum swing speed of an implement is an important performance parameter in many sports. It is understood that moment of inertia (MOI) has an effect upon the swing speed of an implement and numerous studies have found a very similar relationship between swing speed and MOI. These different studies considered different movements which suggested that skill was less important than physique to this relationship. The aim of this work was to quantify the relationship between swing speed and moment of inertia and to determine whether a participant's physical characteristics are related to their swing speed performance. A series of eight visually identical rods, with varied MOI were swung in a heavily restricted, maximal motion. Feedback was supplied to the participants about their motion and all trials were recorded with a Motion Analysis Corporation motion capture system. The results found that a similar exponential relationship exists between swing speed and MOI. It was also found that a participant's maximum work done is significantly related to their swing speed. This is a relationship that could be used to predict a participant's swing speed for a specific MOI implement. More work is to be carried out on a larger population in order to be confident in the power of the relationships found

Dynamic modeling of a springboard during a 3 m dive

Analysis of springboards in elite diving have been limited to the measurement of the variation of material characteristics along the length of the board and it appears that dynamic model of the board's motion have not been carried out because of its complex nature. The purpose of this paper is to develop a simple mechanical model to (i) understand the physics of the board's motion and (ii) act as a precursor to optimizing the board to enable divers to maximize their chances of a good score

Investigating the relationship between swing weight and swing speed across different sports using historical data

In many sports, the maximum swingspeed of a racket, club or bat is a key performance parameter. Previous research has suggested that a logarithmic relationship exists between the resultant swingspeed and the swingweight/moment of inertia of the implement. However, these studies have only focussed on one specific sport and relatively little is known about the effect of swingweight on swingspeedacross the wider spectrum of sport. Data was collated on the swingspeeds achieved in numerous sports that employ an implement and a swinging motion. A range of typical swingweights were determined for the various implements and the data normalised to common conventions such that comparisons could be made. This meta-analysis established a new relationship between swingweight and swing acceleration, valid across the wide range of implements considered. This relationship was found to be of the form a=C/Im, where C is a player constant and m=0.59 (p<0.01)