SUPPORTING THE COACH WITH SCIENCE: THE IRISH EXPERIENCE

Recognising the need for a strong sport science support system, a programme of biomechanical support was set up by Swim Ireland (the Irish Swimming Federation) in 2006. This programme, which forms part of a larger overall inter-disciplinary sport science and medicine service, aims to provide a comprehensive level of biomechanical support for Irish high-performing swimmers and their coaches to enhance performance at elite level. At the centre of the biomechanics programme is the swimmer-coach unit; their performance needs are critical. The scientist’s role is to provide the coach with useful, user-friendly and objective evidence upon which the coach can make effective informed training decisions. Both qualitative and quantitative biomechanical assessment techniques are used to analyse swimmers in training and competition, which typically require the use of above and below water digital video recordings. Suitable intervention strategies for modifying swimming techniques, where necessary, can then be implemented and regularly monitored for effectiveness. The aim of this presentation is to provide an overview of the biomechanics support programme being provided to elite Irish swimmers and their coaches, with particular reference to: 1) competition analysis; and 2) two-dimensional video analysis. Such examples encourage the use of evidence-based coaching

EFFECT OF RELAY CHANGEOVER POSITION ON SKATING SPEED FOR ELITE SHORT TRACK SPEED SKATERS

Relay changeovers in short track speed skating take place when the incoming skater pushes the outgoing skater at the start of the straight. Time can be gained or lost during these changeovers, depending on how effectively they are executed. The position on the track where initial contact between skaters is made is thought to be a critical factor in an effective relay changeover (Riewald et al., 1997). The aim of this study was to determine how the position of the relay changeover on the track would affect skating speed (SS)

STROKE PARAMETERS AND ARM COORDINATION IN COMPETITIVE UNILATERAL ARM AMPUTEE FRONT CRAWL SWIMMERS

The aims of this study were to: (1) determine the changes in stroke parameters and arm coordination as a function of swimming speed; and (2) examine the relationships between stroke parameters and arm coordination, for competitive unilateral arm amputee front crawl swimmers. Thirteen highly-trained swimmers (3 male, 10 female) were filmed underwater from lateral views during six increasingly faster 25 m front crawl trials. Increases in swimming speed were achieved by an increase in stroke frequency which coincided with a decrease in stroke length. All swimmers showed asymmetric coordination between their affected and unaffected arm pulls, which was not affected by an increase in swimming speed up to maximum. The fastest amputee swimmers used higher stroke frequencies and less catch-up coordination before their affected arm pull, when compared to the slower swimmers. Reducing the time delay before initiating the affected arm pull appears to be beneficial for successful swimming performance

Biomechanical characteristics of highly-trained single-arm amputee front crawl swimmers

The general aim of this thesis was to contribute to the body of scientific knowledge regarding the biomechanical characteristics of highly-trained single-arm amputee front crawl swimmers, thus allowing for the application of this knowledge to enhance swimming performance. With this in mind, five experimental studies were undertaken, which focused on three main areas: Firstly, how swimmers adjusted their stroke parameters in order to swim faster and which of the swimmers’ anthropometric characteristics were related to performance. Secondly, what inter-arm and leg-to-arm coordination patterns were exhibited by these swimmers and how inter-limb coordination was related to the attainment of maximum swimming speed. Thirdly, what three-dimensional arm movements were used by these swimmers during the front crawl stroke cycle and how these movements contributed to propulsion and as a consequence the overall progression of the swimmers through the water. The findings of this thesis suggest that when single-arm front crawl swimmers are sprinting: (a) the attainment of a high stroke frequency is more important than swimming with the longest possible stroke; (b) reducing the length of time the affected-arm is held stationary in front of the body will help attain a high stroke frequency; (c) the rhythmical alignment of leg kicks to arm strokes may enhance performance and contribute to the stability of inter-arm coordination; (d) amputees use a more linear underwater hand movement, than able-bodied swimmers and use one of three distinct movement patterns to pull their affected-arm through the water; (e) increases in intra-cyclic swimming velocity can be achieved with the unaffected-arm, but not so with the affected-arm. The findings of this thesis will be of interest to scientists working in the area of swimming biomechanics. They should also be of some practical benefit to unilateral arm-amputee front crawl swimmers and to those who coach and teach them

Measuring straight time in elite short track speed skating relays

In short track speed skating, the relay exchange provides an additional strategic component to races by allowing a team to change the skater involved in the pack race. It is thought that during this period of the race, time can be gained or lost due to the execution of the relay exchange. However, the only temporal measurement reported in short track speed skating is lap time, of which the relay exchange accounts for less than 30 %. As such, a more appropriate measurement of relay exchange performance might be the time taken to complete the straight where the relay exchange was executed. The aim of this study, therefore, was to validate a method for measuring straight time during elite short track speed skating relays. The proposed method used a single HD camcorder to create virtual timing gates at the start and end of both straights. To validate the method, straight times measured using the single HD camcorder were compared to synchronised cameras located perpendicular to the virtual timing gates. The root mean square error for both near and far straight times was less than the temporal resolution of the camera. In addition, Bland-Altman plots showed that the single HD camcorder method was invariant to race speed. Collectively, these findings suggest that a single HD camcorder does provide a valid method for measuring straight times during elite short track speed skating relays

London 2012 Paralympic swimming: Passive drag and the classification system

Background: The key difference between the Olympic and Paralympic Games is the use of classification systems within Paralympic sports to provide a fair competition for athletes with a range of physical disabilities. In 2009, the International Paralympic Committee mandated the development of new, evidence-based classification systems. This study aims to assess objectively the swimming classification system by determining the relationship between passive drag and level of swimming-specific impairment, as defined by the current swimming class. Methods: Data were collected on participants at the London 2012 Paralympic Games. The passive drag force of 113 swimmers (classes 3-14) was measured using an electro-mechanical towing device and load cell. Swimmers were towed on the surface of a swimming pool at 1.5 m/s while holding their most streamlined position. Results: Passive drag ranged from 24.9 to 82.8 N; the normalised drag (drag/mass) ranged from 0.45 to 1.86 N/kg. Significant negative associations were found between drag and the swimming class (τ=-0.41, p<0.01) and normalised drag and the swimming class (τ=-0.60, p<0.01). The mean difference in drag between adjacent classes was inconsistent, ranging from 0 N (6 vs 7) to 11.9 N (5 vs 6). Reciprocal Ponderal Index (a measure of slenderness) correlated moderately with normalised drag (rP=-0.40, p<0.01). Conclusions: Although swimmers with the lowest swimming class experienced the highest passive drag and vice versa, the inconsistent difference in mean passive drag between adjacent classes indicates that the current classification system does not always differentiate clearly between swimming groups

Motivations and barriers to prosthesis users participation in physical activity, exercise and sport : a review of the literature

The UK will host the Paralympics in 2012 and the Commonwealth Games in 2014 showcasing the talents of elite athletes and aiming to inspire the population to become involved. However, low levels of physical activity (PA) are prevalent: only 40% of men and 28% of women meet the minimum UK recommendations. The limb absent population is no exception. To determine if people with limb amputations are participating in physical activity and sport; whether post-amputation activity levels match pre-amputation levels; and if there are motivations and barriers to participation. Study design: Literature review Five reviewers systematically search of peer reviewed and gray literature in seven bibliographic databases and the Cochrane Library. Results: Following rigorous elimination, 12 articles were finally included in the review and critically appraised. Four themes were identified: components, rehabilitation outcomes, body image and motivations and barriers to participation. People with limb absence are not participating in PA conducive to health benefits, and only a minority participate in exercise and sports. Participation following amputation does not mirror that of pre-amputation levels, and more barriers than motivations exist to adopting and maintaining a physically active lifestyle. This literature review aims to inform those involved in rehabilitation and ongoing care of those with limb absence about what motivates or precludes their participation in physical activity, exercise and sport. Such knowledge could be applied to improving health and well being in this population