A paradigm for identifying ability in competition: The association between anthropometry, training and equipment with race times in male long-distance inline skaters - the ‘Inline One Eleven’

Purpose. The association between anthropometric and training characteristics on an athlete’s performance has been investigated in swimmers, cyclists and runners, but not in inline skaters. The aim of this study was to investigate the relationship between anthropometry, pre race preparation and equipment in the finishers of the longest inline race in Europe, the ‘Inline One eleven’ over 111 km in Switzerland. Basic procedures. We investigated the association of anthropometry, training, and equipment variables with race times in 84 male ultraendurance inline skaters using bi- and multivariate analysis. Main findings. In the multivariate analysis, percent body fat, duration per training unit, and personal best time in the ‘Inline One eleven’ was related to the race time for all finishers. Out of the 84 finishers, 58 had already finished an ‘Inline One eleven’ while 26 participated for the first time. Speed in training and the kind of skates worn were related to race times of the 26 inexperienced finishers. The inexperienced finishers skating with custom made skates were significantly faster with 229.1 (12.7) min compared to inexperienced finishers using ordinary skates finishing within 290.8 (35.4) min ( p < 0.001). For experienced inliners, body mass, the sum of skin-folds and percent body fat correlated to race time. Conclusions. We assume that inexperienced athletes in ultra-endurance skating need time to gain the experience necessary in choosing the correct equipment and doing the training in order to successfully finish a long-distance inline race. Experienced inliners can only improve race performance in an ultra-endurance inline race such as the ‘Inline One eleven’ through a reduction of their body fat

Low prevalence of exercise-associated hyponatremia in male 100km ultra-marathon runners in Switzerland

We investigated the prevalence of exercise-associated hyponatremia (EAH) in 145 male ultra-marathoners at the ‘100-km ultra-run' in Biel, Switzerland. Changes in body mass, urinary specific gravity, haemoglobin, haematocrit, plasma [Na+], and plasma volume were determined. Seven runners (4.8%) developed asymptomatic EAH. Body mass, haematocrit and haemoglobin decreased, plasma [Na+] remained unchanged and plasma volume increased. Δ body mass correlated with both post race plasma [Na+] and Δ plasma [Na+]. Δ plasma volume was associated with post race plasma [Na+]. The athletes consumed 0.65 (0.30) L/h; fluid intake correlated significantly and negatively (r=−0.50, p<0.0001) to race time. Fluid intake was neither associated with post race plasma [Na+] nor with Δ plasma [Na+], but was related to Δ body mass. To conclude, the prevalence of EAH was low at ~5% in these male 100km ultra-marathoners. EAH was asymptomatic and would not have been detected without the measurement of plasma [Na+

What influences race performance in male open-water ultra-endurance swimmers: anthropometry or training?

We investigated the relationship between selected variables of anthropometry and training with race performance during a 26.4 km open-water ultra-endurance swim at 23 °C in male master ultra-swimmers. Basic procedures. Fifteen non-professional male open-water ultra-endurance swimmers who were (mean ± SD) 40.0 (8.2) years of age with 83.7 (10.3) kg body mass, 1.80 (0.08) m body height and a BMI of 25.5 (2.5) kg/m2 finished the race within the time limit. Body mass, percent body fat, thickness of 7 skin folds, body height, length of arm, and length of leg were measured prior to race. The number of years as active swimmer, average weekly training volume in hours and kilometres and average speed in training were recorded. The variables were then correlated to total race time. Main findings. Study participants had mean finish times of 551 (100) min and an average speed of 3.0 (0.5) km/h. Speed in swimming during training was the only variable related to total race time (r = –0.66, p = 0.0037) whereas none of the other investigated variables showed an association. Conclusions. We conclude that anthropometry was not related to race performance in these male ultra-endurance swimmers whereas speed in training showed a moderate association with total race time

Nutrition in ultra-endurance racing - aspects of energy balance, fluid balance and exercise-associated hyponatremia

Ultra-endurance athletes try to extend their limits in performance. In ultra-endurance races, athletes face limits in nutrition regarding both energy intake and fluid metabolism. The purpose of this review is to focus on the decrease in body mass, aspects of energy and fluid balance, and exercise-associated hyponatremia in ultra-endurance performance. An ultra-endurance performance lasting 24 hours or longer may lead to an energy deficit of approximately 7,000 kcal per day. This energy deficit may result in a decrease of body mass, including a decrease in both fat mass and skeletal muscle mass. The energy deficit cannot be completely compensated by increasing energy intake. Adequate fluid intake is required during an ultra-endurance performance to prevent dehydration. In case of fluid overload, both exercise-associated hyponatremia and swelling of limbs may occur. Limited fluid intake of approximately 300-400 ml per hour may prevent both exercise-associated hyponatremia and swelling of limbs. In summary, in ultra-endurance performances, an energy deficit seems to be unavoidable, and athletes are at risk to develop both exercise-associated hyponatremia and limb swelling in case of fluid overload

No case of exercise-associated hyponatraemia in top male ultra-endurance cyclists: the ‘Swiss Cycling Marathon'

The prevalence of exercise-associated hyponatraemia (EAH) has been investigated in endurance athletes such as runners and Ironman triathletes, but not in ultra-endurance road cyclists. We assessed fluid intake and changes in body mass, urine specific gravity and plasma sodium concentration ([Na+]) in 65 ultra-endurance road cyclists in a 720-km ultra-cycling marathon, the ‘Swiss Cycling Marathon'. The cyclists lost 1.5 (1.7)% body mass (P<0.01). No athlete developed EAH. Fluid intake was associated with the change in plasma [Na+] (r=−0.32, P<0.05) and the change in body mass (r=−0.30, P<0.05). The change in plasma [Na+] was related to post-race plasma [Na+] (r=0.63, P<0.0001). To conclude, ad libitum fluid intake in ultra-endurance cyclists in a single-stage ultra-endurance road cycling race showed no case of EAH. Future studies regarding drinking behaviour in different ultra-endurance disciplines might give insights into why the prevalence of EAH is different in the different discipline

Higher prevalence of exercise-associated hyponatremia in female than in male open-water ultra-endurance swimmers: the ‘Marathon-Swim' in Lake Zurich

We investigated the prevalence of exercise-associated hyponatremia (EAH) in 25 male and 11 female open-water ultra-endurance swimmers participating in the ‘Marathon-Swim' in Lake Zurich, Switzerland, covering a distance of 26.4km. Changes in body mass, fat mass, skeletal muscle mass, total body water, urine specific gravity, plasma sodium concentration [Na+] and haematocrit were determined. Two males (8%) and four females (36%) developed EAH where one female was symptomatic with plasma sodium [Na+] of 127mmol/L. Body mass and plasma [Na+] decreased (p<0.05). The changes in body mass correlated in both male and female swimmers to post-race plasma [Na+] (r=−0.67, p=0.0002 and r=−0.80, p=0.0034, respectively) and changes in plasma [Na+] (r=−0.68, p=0.0002 and r=−0.79, p=0.0039, respectively). Fluid intake was neither associated with changes in body mass, post-race plasma [Na+] or the change in plasma [Na+]. Sodium intake showed no association with either the changes in plasma [Na+] or post-race plasma [Na+]. We concluded that the prevalence of EAH was greater in female than in male open-water ultra-endurance swimmer

Skin-fold thickness and race performance in male mountain ultra-marathoners

Recent studies showed in high level runners both an association between selected skin-fold thicknesses at the lower limb and running performance and between thickness of skin-fold and training. We investigated the association of skin-fold thicknesses with total race time in 25 male mountain ultra-marathoners with 44.5 (7.0) years, 73.0 (7.8) kg body mass, 1.78 (0.07) m body height and a BMI of 22.9 (1.8) kg/m2 in a 7-day mountain ultra-marathon over 350 km with 11,000 m of altitude. The relationship of skin-fold thickness and both intensity and volume during training with total race time as the dependent variable was investigated using multiple linear regression analysis. A significant association of the calf skin-fold with total race time was found (r2 = 0.19, p < 0.05). No relationship between skin-fold thickness and both average running speed and volume in training could be demonstrated. We concluded that the calf skin-fold showed a small to moderate association with total race time, however, the thickness of calf skin-fold was not related to training parameters

The influence of arginine supplementation on performance and metabolism in athletes

Objective: The aim of this review was to investigate the effects of supplementation with arginine, mainly in combination with aspartate and/or other potentially ergogenic amino acids, on metabolism of substrates, endocrine parameters and performance in endurance and resistance athletes. Data sources: The database PUBMED was consulted, using the following keywords "arginine", "aspartate", "performance" and "metabolism". The references in these articles were scanned for further relevant publications. Study section: Studies with oral or intravenous administration of arginine and/or aspartate alone or in combination with other amino acids were selected. Data extraction: Studies with at least six subjects and utilising a placebo-controlled design were analysed. Data synthesis: Seven studies with the combination of arginine aspartate and evaluation of the effect on performance in athletes were found and evaluated. In addition, further studies with arginine and combination with other amino acids were found and analysed in the same manner. Conclusions: No effect on selected parameters of metabolism or the endocrine system have been shown after oral or intravenous arginine, arginine aspartate or other combinations with arginine and aspartate. Neither were there any ergogenic effects in trained athletes after oral or intravenous arginine use, either alone or in combination with aspartate and/or other potentially ergogenic amino acids

Immunity to MHC class I antigen after direct DNA transfer into skeletal muscle.

Plasmid cDNA encoding the alpha-chain of either membrane-bound (pcRT.45) or secreted (pcRQ.B3) RT1Aa MHC class I Ag were transferred to Lewis (RT1(1)) rat skeletal muscle by direct injection. Rats were challenged 7 days later with an ACI (RT1a) heterotropic heart transplant, and cardiac allograft survival, RT1Aa-specific antibody levels, and frequency of ACI-specific CTL were monitored. Graft rejection was accelerated by > or = 2 days in an Ag-specific and dose-dependent manner in pcRT.45-injected rats. The pcRQ.B3-injected rats also rejected grafts more rapidly; however, graft rejection was accelerated by only 1 day, and graft infiltrates were less pronounced than in pcRT.45-injected rats. Injection of pcRT.45 resulted in an increase in ACI-specific CTL precursor frequency 3 days post-transplant, whereas there was no significant change in rats pretreated with pcRQ.B3 injection. Compared with rats injected with a control plasmid encoding firefly luciferase, transfer of pcRT.45 resulted in an increase in RT1Aa-specific IgG and IgM antibody 3 days after heart transplantation. Transfer of pcRQ.B3 resulted in a similar mean increase in RT1Aa-specific IgG and IgM antibody after transplantation, but the variability from rat to rat was greater, with some animals exhibiting strong priming, and others showing little or no priming by gene injection. Our results suggest that skeletal muscle can express either membrane-bound or secreted MHC class I Ag after gene transfer, but that the membrane-bound form is more immunogenic than the secreted form in the high responder Lewis rat. Direct DNA transfer to skeletal muscle provides a rapid and specific approach to studying immunity to allogeneic MHC Ag

Induction of specific tolerance by intrathymic injection of recipient muscle cells transfected with donor class I major histocompatibility complex.

Induction of tolerance to allogeneic MHC antigens has been a goal in the field of transplantation because it would reduce or eliminate the need for generalized immunosuppression. Although encouraging results have been obtained in experimental models by exposing recipient thymus to donor cells before transplantation, donor cells are not typically available at that time, and the donor antigens responsible for the effect are poorly defined. In the present study, thymic tolerance was demonstrated without using donor cells. Recipient thymus was injected before transplantation with autologous myoblasts and myotubes that were genetically modified to express allogeneic donor-type MHC class I antigen. Donor-specific unresponsiveness was induced to a completely MHC-disparate liver transplant and to a subsequent donor-type cardiac allograft, but not a third-party allograft. In vitro, recipient CTL demonstrated a 10-fold reduction in killing of donor cells, but not of third-party cells. Our results demonstrate: (1) that recipient muscle cells can be genetically engineered to induce donor-specific unresponsiveness when given intrathymically, and (2) transfected recipient cells expressing only donor MHC class I antigen can induce tolerance to a fully allogeneic donor