Influence of Adventure Race Disciplines on the Overall Performance during 35 to 50-km Races

Abstract Aims: This study aims to analyze the influence of adventure race disciplines on the overall performance during 35 to 50-km competitions. Methods: Twenty-four athletes from twelve teams were studied during the second (Jacarei-SP, Brazil, 44.5-km) and fourth (Passa Quatro-MG, Brazil, 37.1-km) races of the 2015 Haka Race Series, which comprised Brazilian Adventure Race Ranking. We analysed the relationship between disciplines velocities and overall race velocity of the teams during each competition. Results: We observed the race velocity of the teams during second race was significantly (P < 0.05) correlated with the first (R=0.80) and last (R=0.65) split velocities of trekking, and with the last split velocity of mountain biking (R=0.73). On the other hand, the race velocity of teams during fourth race was significantly (P < 0.05) correlated with the split velocity performed during the course of water trekking with trekking (R=0.96). Conclusion: Greater performance of the athletes in the disciplines of mountain biking, trekking and water trekking is related to their overall performance during 35-50 km ARs. In addition, the influence of adventure race disciplines is specific to the overall performance during different competitions.

Hyperproteic supplementation attenuates muscle damage after simulated Olympic cross-country mountain biking competition: a randomized case-control study

Abstract Aim: We investigated the effect of high-protein (HI-PRO - 70% protein and 30% carbohydrate) and high-carbohydrate supplementation (HI-CHO - 70% carbohydrate and 30% protein) on muscle damage, haemoglobin, immune response, perceived pain and recovery post-simulated XCO. Methods: For this,10 amateur athletes (38±9.6 yrs.) were measured pre-, post- and 24-h post-trial. Results: In comparison to the pre-trial, the post-trial athletes presented leucocytosis (p≤0.001; 14.7±6.1 and 13.6±5.6 cells x103; for HI-PRO and HI-CHO, respectively) and neutropenia (p≤0.001; 11.9±5.2 and 10.7±4.9 cells x103; for HI-PRO and HI-CHO, respectively) but recovered at 24-h post-trial (Leukocytes: 6.9±1.4 and 7.1±1.4 cells x103; for HI-PRO and HI-CHO, respectively; neutrophils: 3.6±1.2 and 3.9±1.1 cells x103; for HI-PRO and HI-CHO, respectively) without a difference between conditions (p=0.808 and p=0.531; for leukocytes and neutrophils, respectively). A similar result was observed for perceived pain and recovery, where the condition did not interfere with these variables between the o measurement moments (p=0.245 and p=0.491; for pain and recovery respectively). There was an interaction effect for lactate dehydrogenase (LDH), where HI-PRO presented a lower serum concentration 24-h post-trial compared to HI-CHO (p=0.039; 181.3±21.9 and 201.0±10.4 IU/L; for HI-PRO and HI-CHO, respectively). Conclusion: HI-PRO supplementation results in better muscle damage recovery but only for LDH. Athletes should evaluate the cost-benefit of choosing the nutrients to be consumed immediately post-training or competition.

Do the health benefits of cycling outweigh the risks? / Os benefícios à saúde em andar de bicicleta superam os riscos?

Although from a societal point of view a modal shift from car to bicycle may have beneficial health effects due to decreased air pollution emissions and increased levels of physical activity, shifts in individual adverse health effects such as higher exposure to air pollution and risk of a traffic accident may prevail. We have summarized the literature for air pollution, traffic accidents, and physical activity using systematic reviews supplemented with recent key studies. We quantified the impact on all-cause mortality when 500,000 people would make a transition from car to bicycle for short trips on a daily basis in the Netherlands. We estimate that beneficial effects of increased physical activity are substantially larger (3-14 months gained) than the potential mortality effect of increased inhaled air pollution doses (0.8-40 days lost) and the increase in traffic accidents (5-9 days lost). Societal benefits are even larger because of a modest reduction in air pollution and traffic accidents. On average, the estimated health benefits of cycling were substantially larger than the risks relative to car driving for individuals shifting their mode of transport.

Embora uma mudança do uso de carro para bicicleta possa trazer efeitos benéficos para a saúde devido à diminuição da poluição do ar e a um aumento da atividade física, esta mudança também pode trazer efeitos adversos à saúde como exposição à poluição e risco de acidentes de trânsito, os quais podem superar os benefícios. Nós resumimos a literatura sobre poluição do ar, acidentes de trânsito e atividade física, utilizando revisões sistemáticas suplementadas com estudos recentes. Quantificamos também o impacto na causa de mortalidade se 500 mil pessoas fizessem a transição de carro para bicicleta em viagens curtas diárias na Holanda. Estimamos que os efeitos benéficos do aumento da atividade física são substancialmente maiores do que o efeito potencial da mortalidade por inalação de ar poluído e aumento de acidentes de trânsito. Os benefícios sociais são ainda maiores devido a uma modesta redução na poluição do ar e nos acidentes de trânsito. Em média, os benefícios de saúde devido ao uso da bicicleta são substancialmente maiores do que os riscos relativos a dirigir um carro para pessoas em transição do modo de transporte.