Team New Zealand, America s Cup Challenge 2003, Auckland, New Zealand

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1 anthropometry Anthropometric dimensions of Team New Zealand America s Cup sailors Simon Pearson 1, Patria A Hume 1, Peter Mellow 1, David Slyfield 2 1 Institute of Sport and Recreation Research New Zealand, Faculty of Health and Environmental Sciences, Auckland Correspondence Assoc Prof Patria Hume PhD Director, Institute of Sport and Recreation Research New Zealand Faculty of Health & Environmental Sciences Auckland University of Technology Private Bag Auckland NEW ZEALAND Phone Ext 7306 Fax patria.hume@aut.ac.nz University of Technology, New Zealand 2 Team New Zealand, America s Cup Challenge 2003, Auckland, New Zealand ABSTRACT The aim of this study was to describe the anthropometric dimensions of the crew members in an America s Cup Sailing team with the study design being cross-sectional descriptive. Measures were taken during the Team New Zealand syndicate s 2003 America s Cup campaign. Thirty-five male Team New Zealand America's Cup sailors (12 grinders, 7 trimmers, 11 afterguard, and 5 bowmen), with an of 19 years sailing experience. Outcome measures; participants were measured for 40 anthropometric dimensions (using ISAK protocols) including skinfolds, muscle girths and segment lengths. Grinders were significantly larger than other sailing groups in a number of anthropometric measures including height, body mass, various limb and bone measurements, and skinfolds. The larger standing height for the grinders was due to a longer tibia and not from a longer femur or longer trunk. Twelve of 13 girths were significantly larger in grinders than in any other sailor groups. Grinders had significantly more lean muscle mass than all other sailing groups. The largest lean muscle mass was kg for a grinding sailor of kg (1% body fat). Sailors in afterguard, trimming and bow groups showed very few differences in anthropometric characteristics between them. America s Cup sailors with a primary on-board function of grinding have significantly different anthropometric dimensions to sailors in the trimmer, afterguard or bow positions. Keywords: anthropometry, America's Cup sailors, grinders, trimmers, afterguard, bowmen. SMNZ Street Address NZ Sports Academy SI 40 Logan Park Drive Dunedin New Zealand NZJSM, P52 The America's Cup sailing regatta was first raced in 1851 as an American challenge to the nautical supremacy of the British. Following the American victory in the inaugural competition the America's Cup did not leave the United States for 132 years until the successful Australian challenge of The Cup then returned to the United States in 1986 before being won by the Team New Zealand America's Cup challenge in In the year 2000, Team New Zealand became the only syndicate to successfully defend the America's Cup outside of the United States, and in February 2003 unsuccessfully attempted to repeat this effort. As one of the most well established and also most technologically advanced regattas in the world, the America's Cup is generally considered to be the pinnacle of sailing competition. There is limited sport science literature on America's Cup sailing in any field, and therefore anthropometric data are scarce. A physiological study of sailors in small sailing craft by Shephard 14 reported anthropometric data, and recommended that for Olympic sailing boats in high wind conditions, the

2 skipper should be light (less than 60 kg) but crewmembers should be heavy (greater than 80 kg). Shephard 14 also stated that height was not a great advantage to the crew, possibly because they lacked the muscular strength to exploit the added leverage. In longer forms of racing, Branth 4 estimated energy turnover in crew members of one team during the Whitbread Round the World Race using anthropometric measurements in conjunction with dietary intake, but the relevance of this information to match-racing is negligible. At the time of writing the only available anthropometric data on America s Cup sailors are from Bernadi 3 who recorded height, weight, and percentage body fat during their physiological profiling of the Mascalzone Latino 2003 challenge. Anthropometric characteristics, reflecting body shape, proportionality and composition, can suggest a functional advantage in some sports 12. If body anthropometrical characteristics are significantly related to sailing performance, then sailing teams can select athletes with anthropometric dimensions more suited to perform the sailing manoeuvres to enhance their likelihood of competitive success. An understanding of the anthropometric characteristics of sailors may also help in the development of specific resistance training programmes. The anthropometric characteristics of the sailors will vary depending on the physical skills required in the sailing position. For example, shortness in stature is particularly advantageous in acceleration 7 while activities requiring greater upper body strength show an extreme sitting height to standing height ratio 12. Grinders The sailors known as grinders use the handles on a mechanical grinding pedestal to drive the winches attached to the sail lines, which are responsible for the movement of the sails - the propulsive force behind the yacht. A large amount of resistance is placed on the grinding system due to the many tonnes of pressure held in the sails. As a result, it can often be very difficult to turn the cranks even with the different gears available through the grinding system. Grinders not only need muscular power but also muscular endurance because the explosive forces needed for a single tack or trimming of the sails must be produced repetitively over the course of a race. The performance of a grinder is best defined by the amount of power that can be produced. This was defined for a cyclic movement by Hull and Gonzalez 10 as the product of applied force, length of the crank arm and angular velocity of the movement (P = F x L x w). Applied force is mainly dependent on the human component and would therefore be affected by factors such as body mass, neuromuscular control (strength/ coordination), height, arm length, leg length, and brachial index (comparative forearm and upper arm segment lengths). An individual s anthropometry or physical characteristic is likely to influence their grinding performance, both through force generation and helping to determine the length of the effective lever arm. Trimmers The main responsibility of an America s Cup trimmer is to fine-tune the shape of the sails in order to maximise the performance of the boat, by using ropes (sheets). Trimmers require a detailed knowledge of the rigging and understanding of the tactics being employed, as well as general fitness and endurance (both physical and mental) in order to maintain performance over the course of the race. Trimmers are also involved in assisting on the grinding pedestals, and although their contribution is low (5-10% of total role) a certain amount of muscular power is also a necessary physical attribute. Afterguard Afterguard are often referred to as the brain s trust and are the decision-makers on board an America s Cup yacht. Amongst the afterguard there are a number of separate roles - the tactician, navigator, helmsman, and strategist/traveller. The tactician is responsible for the positioning of the boat on the course according to the weather and race conditions, working very closely with the navigator, who is responsible for the electronic navigational equipment, and the strategist, who is the spotter for any wind shifts. The helmsman takes information from the other members of the afterguard and is then responsible for directing the boat, in order to optimise its position. While these positions are predominantly mentally rather than physically challenging, general fitness is also beneficial for maintaining alertness over long periods. In addition, all members of the afterguard (with the exception of the helmsman) may at some stage in the race be called on to assist on the grinding pedestals, and although their contribution (0-15%) varies greatly according to their primary role, muscular power is a beneficial physical attribute. Bowmen Bowmen are primarily responsible for the organisation, packing and maintenance of the sails and rigging on the boat, but also assist the grinders in hoisting and dropping sails and general grinding work when possible, which usually makes up 20-30% of their role. Bowmen are therefore required to possess muscular strength and power for grinding and for moving sails around above and below deck. But more than any other position, bowmen also need to be agile as much Vol 33, No 2, P53

3 SMNZ Street Address NZ Sports Academy SI 40 Logan Park Drive Dunedin New Zealand NZJSM, P54 of their time is spent out on the narrow bow of the boat, organising sails, spinnaker poles and judging distances when manoeuvring in close quarters with another boat (especially in the pre-start). AIM This study aimed to describe the anthropometric dimensions for the crewmembers in the 2003 Team New Zealand America s Cup Sailing team. METHODS The Auckland University of Technology Ethics Committee approved this study. All sailors received verbal and written information about the study and gave written informed consent prior to anthropometric measurement. Thirty-five male Team New Zealand America s Cup sailors (12 grinders, 7 trimmers, 11 afterguard, and 5 bowmen), with an of 19 years sailing experience, were measured for 40 anthropometric dimensions (using ISAK protocols) during the 2003 campaign. All measures were taken at the beginning of the campaign (November 2000), with measures subject to training induced changes (body mass, skinfolds, muscle girths) tracked throughout the campaign. Variables reported in this study relating to body composition are based on the final assessment of the campaign (December 2002) and therefore represent the end of their training cycle, or optimum competition condition. Double measures for each of the 40 anthropometric dimensions were obtained using the International Society for the Advancement of Kinathropometry (ISAK) protocols 12 and included eight skin-folds (using a Slimguide calliper 10 g/mm 2 constant pressure), 13 limb/body girths (using a Lufkin metal tape), 11 limb/body lengths (using an anthropometer), four breadths and widths, and body mass (using Seca scales). All unilateral measures were taken on the right side of the body by anthropometrists with ISAK Level 2 accreditation or higher (technical error of measurement less than 1% for all measures). Selected anthropometric measures were used to determine somatotype following the methods described by Heath and Carter 9, and body composition using the methods of Drinkwater and Ross 6. Musculoskeletal size was measured by dividing fat free body weight by height 15. The Brugsch chest stature index (chest circumference/ height), acromio-iliac index (bi-iliac/bi-acromial breadth), cormic index (sitting height/standing height), stout-lean index (weight/standing height), arm lengthheight index (arm length/standing height), crural index (tibia length/femur length), brachial index (forearm length/upper arm length), arm-leg index (arm length/ leg length) and forearm-tibia index (forearm length/ tibia length) were calculated. For the purposes of comparison and discussion the 35 sailors were divided into functional sailing categories of grinder, trimmer, afterguard, and bowmen. Results are expressed as mean (± standard deviation). A one-way ANOVA was used for comparison among groups with the a priori level of statistical significance set at p < RESULTS The anthropometric characteristics of the Team New Zealand America s Cup sailors are shown in Table 1. The grinder sailors were significantly taller, heavier, had a larger arm span, longer forearm and hand length, and longer feet, than the other three groups of sailors. However, the sitting height was only different between the grinder and trimmer groups, with neither the after-guard or bow groups showing a difference with the other groups. The larger standing height for the grinders was due primarily to a longer tibia and not from a longer femur or longer trunk. The grinders also had wider humeral bones, femoral bones, and hips than all the other groups of sailers, and wider chest and shoulders than members of the bow and afterguard. Twelve of the 13 girths were significantly larger in the grinders than in any other sailor groups. Sum of skinfolds were similar between the trimmer (78 ± 21 mm), after-guard (84 ± 17 mm), and bowmen (79 ± 15 mm) groups, but were significantly higher in the grinder group (102 ± 15 mm, p < 0.015). There was a significant correlation between sum of skin-folds and body mass (r = 51, p = 0.001) and between fat free mass and sum of skin-folds (r = 0.455, p < 0.006). Grinders had significantly more lean muscle mass than all other sailing groups. The largest lean muscle mass was kg for a grinding sailor of kg (1% body fat). The sailors in the afterguard, trimming and bow groups showed very few differences in anthropometric characteristics between them. DISCUSSION Anthropometric characteristics of grinders were significantly different to those for sailors in any other position on the boat, with the grinding group being larger in almost all linear measures of body shape. This is probably due to the nature of the tasks performed by each position during sailing. The primary function of a grinder is to provide the power for the mechanical grinding winches that control the movement of the sail, hence why the grinders are sometimes referred to as the engine of the boat. In comparison, although most crewmembers will be required to grind at some stage

4 Table 1: Summary anthropometric characteristics for eleven America's Cup sailing grinders. Age (years) Weight (kg) Standing height (cm) Sitting height (cm) Arm span (cm) Segment lengths (cm) Acromiale-radiale Radialie-stylion Midstylion-dactylion Iliospinale Trochanterion Trochanterion-tibiale laterale Tibiale laterale Tibiale mediale-sphyrion tibiale Foot length Breadths(cm) Biacromial Transverse chest Anterior-posterior chest Biliocristale Humeral (biepicondilar) Femoral (biepicondilar) Girths (cm) Head Neck Arm (relaxed) Arm (flexed and tensed) Forearm (maximum) Wrist (distal styloids) Chest (mesosternale) Waist (minimum) Gluteal (hips) Thigh (1cm gluteal) Thigh (mid) Calf (maximum) Ankle (minimum) Calculated variables Sum of 7 skinfolds (mm) Drinkwater & Ross fat (%) Lean mass (kg) Lean mass (%) Musculo-skeletal size Height to weight ratio Endomorphy Mesomorphy Ectomorphy Brachial index (%) Acromio-iliac index (%) Cormic index (%) Stout-lean index (%) Arm length-height index (%) Crural index (%) Arm-leg index (%) Forearm-tibia index (%) Brugsch chest stature (%) Grinder n= ,3, ,3, ,3, ,3,4 2 2,3, ,4 4 3, ,3, , , ,3, ,3,4 1 2,3, , ,3,4 4 2,3, ,3, ,3, ,3, ,3, ,3, ,3, ,3,4 4 2,3, ,3, ,3, ,3, ,3, ,3,4 2,3, ,3, ,3, Trimmer n= Afterguard n= , , Bow n= Significantly different to grinder group. 2 Significantly different to trimmer group. 3 Significantly different to afterguard group. 4 Significantly different to bow group. in a race, their primary responsibilities have either slightly less or at least different physical demands to those of the grinders. In terms of limb length, shorter limbs can be useful for strength athletes because shorter levers are required to perform less work where the mass is lifted through a smaller distance 12. However, longer segment lengths can also be beneficial for force application, as they will provide greater leverage and increased torque. There is also a potential benefit in terms of muscular, and therefore strength, development. Longer limb lengths are more beneficial for grinding, with significantly longer lengths occurring in the grinder group when compared to the other three groups. An additional characteristic that may affect grinding is Vol 33, No 2, P55

5 SMNZ Street Address NZ Sports Academy SI 40 Logan Park Drive Dunedin New Zealand brachial index (BI), which is a measurement of forearm length relative to upper arm length (BI = radius length/ humerus length x 100). The BI is reported to influence leverage properties of the upper limb 12, and the force applied by the hands. Given that backward grinding is predominantly a pulling activity, a higher brachial index (representing a relatively shorter humerus) would be considered beneficial as a relatively shorter upper arm should allow the hand to travel in a more linear path, in an activity where only straight-line forces are beneficial. Hahn 8 found that highly ranked rowers had significantly longer forearms than other rowers, while having no significant difference in upper arm length. This would result in a higher brachial index in the highly-ranked rowers. However, there were no differences in BI between the grinder group and the other three groups of America s Cup sailors. Body fractionation methods allow estimates of lean muscle mass and fat mass. Brechue 5 examined the role of free fat mass accumulation and skeletal muscle architecture in competitive power-lifting performance by 20 US male elite power-lifters. Fat free mass was strongly correlated to the lift performances (r = 6-5, p < 0.001). Greater fascicle lengths were associated with greater fat free mass accumulation (r = 9-3, p < 0.01) and power-lifting performance (r = , p < 0.05). Brechue 5 concluded that greatest absolute power-lifting performance was limited by fat free mass accumulation in elite power-lifters. The largest lean muscle mass for any sailor (103.8 kg) was less than a power-lifter reported by Brechue 5 who had kg fat free mass at a body mass of kg (36.3% body fat), although the percentage body fat for the grinding sailor was less than the power-lifters. In power-lifting low fat levels are desirable since competitors are allocated to specific weight categories, so their weight must be useful muscle mass rather than fat mass 2. In the America s Cup competition there is a weight restriction for the sailing crew so gains or changes in body mass of an individual must be balanced through the entire team. Therefore, maximising the proportion of functional muscle mass to fat mass, which has little functional benefit, is an important crew selection consideration. There is a linear relationship between height and fat free mass until a height of approximately 1.7 m where the relationship appears to level off 1. In estimating body composition, it is preferred that sum of skin-folds are reported 11. After-guard tended to have a higher sum of skin-folds (84 ± 16 mm) than either the bowmen (79 ± 15 mm) or the trimmers (78 ± 21 mm). Absolute fat-free (functional) mass was lower in the bow group, but the relative fat-free mass (89.1 ± %) was the second highest of all four sailing groups, only just behind the trimmers (89.4 ± %). These findings are consistent with those of Bernadi 3 in their study of the Mascalzone Latino crew. A group classified as all others (assumed to be made up of the after-guard) had a higher body fat percentage than the grinders, bowmen, or trimmers. The higher level of body fat is most likely a function of the lower levels of physical activity required of the after-guard during sailing than is required of the bowmen or the trimmers. As the principle role of the after-guard is tactical, which requires attention to be focussed predominantly on the conditions of the race, the afterguard will tend to spend less time involved in tasks requiring strenuous physical work than other crew members. Consequently, their energy expenditure and muscular stimulation is likely to be lower, resulting in relatively higher levels of fat storage compared to muscle mass. The grinders had larger mesomorphy and ectomorphy somatotype ratings compared with the other groups of sailors. The grinding group has been shown to have significantly different characteristics from the other positions on the boat. In comparison, the trimmer, after-guard, and bowman groups showed very few significant differences between them despite a large amount of variation in the tasks performed. Significant differences were larger transverse chest (p=0.04) and waist girth (p=0.020) measures in the after-guard compared to the bow group, and a larger medial calf skin-fold (p=0.032) in the after-guard compared to the trimmers. However, just because differences were not significant does not mean they were not present, and there were some additional trends shown that perhaps give a better indication of the differences between these groups. The sailors in the bow positions tended to have lower total body mass, lower fat-free mass, and slightly smaller girths than both the trimmers and the after-guard. Practical Applications The most specialised position within an America s Cup crew in terms of physical attributes is undoubtedly that of the grinders. The primary requirement of strength means that in terms of identifying a potential grinder, the ability to generate muscle-mass and therefore develop strength is at a premium. Because of the association of fat-free mass accumulation with fascicle length, bone dimension measures are likely to provide a valuable indication of the ability to build muscle mass and strength. Bowmen are the other group who could be identified by physical characteristics. As their primary work on the boat involves balance and work in confined spaces, they would be considerably NZJSM, P56

6 advantaged by a smaller frame, in addition to high levels of agility, while maintaining strength. CONCLUSIONS Sailors in different functional positions in the Team New Zealand America s Cup sailing crew had different anthropometric dimensions, which reflected the physical tasks required of them during a sailing race. Grinders showed significant differences in anthropometry from all other groups, and while there were also differences between the trimmer, afterguard, and bowmen groups, they were much less pronounced. Physical attributes and anthropometric screening may help to identify top-level grinders and bowmen. Cup , Toronto, Canada: Warwick Publishing. 14 Shephard R J. The biology and medicine of sailing. Sports Med, 1990; 9(2): Slaughter M H and Lohman T G. Lean body mass in relation to height in athletes. In M. Ostyn, G. Beunen & J. Simons (Eds.), Kinanthropometry II, 1980 (pp ). Baltimore: University Park Press. ACKNOWLEDGEMENTS Auckland University of Technology funded this study. Thanks are given to the sailors in the Team New Zealand America s Cup Challenge , and to the six anthropometrists who helped with data collection. REFERENCES 1 Abe T, Brechue W F, Fujita S and Brown J B. Gender differences in FFM accumulation and architectural characteristics of muscle. Med Sci Sports Ex, 1998; 30(7): Bale P and Williams H. An anthropometric prototype of female power lifters. J Sports Med Phys Fit, 1987; 27(2): Bernadi M, Fontana G, Rodio A, Madaffari A, Brugnoli M and Marchetti M. Physiological characteristics of America s Cup sailors, Paper presented at the Human Performance in Sailing Conference, Auckland, New Zealand. 4 Branth S, Hambreaus L, Westerterp K, Andersson A, Edsgren R, Mustelin M, et al. Energy turnover in a sailing crew during offshore racing around the world. Med Sci Sports Ex, 1996; 28(10): Brechue W F and Abe T. The role of FFM accumulation and skeletal muscle architecture in powerlifting performance. Europ J Appl Physiol, 2002; 86(4): Drinkwater D T and Ross W D. Anthropometric fractionation of body mass. In M Ostyn, G Beunen and J Simons (Eds), Kinanthropometry II, 1980 (pp ). Baltimore: University Park Press. 7 Ford L E. Some consequences of body size. Am J Physiol, 1984; 247(4 Pt 2):H Hahn A. Identification and selection of talent in Australian rowing. Excel, 1990; 6(3): Heath B H and Carter JEL. A modified somatotype method. Am J Phys Anthrop, 1967; 27(1): Hull M L and Gonzalez H. Bivariate optimization of pedalling rate and crank arm length in cycling. J Biomech, 1988; 21(10): Huygens W, Claessens A L, Thomis M, Loos R, Van- Langendonck L, Peeters, M, et al. Body composition estimations by BIA versus anthropometric equations in body builders and other power athletes. J Sports Med Phys Fit, 2002; 42(1): Norton K, and Olds T (Eds). Anthropometrica : A textbook of body measurement for sports and health courses, Sydney: University of New South Wales Press. 13 Rayner R and Thompson T. The Story of the America s Vol 33, No 2, P57