University of Alcalá

The adoption of policies promoting physical activity has increased over the last two decades, but there is limited evidence that these policies are being implemented, and physical inactivity has remained high during this period, says an article published in Nature Health. The study is based on an analysis of documents from 200 countries and interviews with 46 experts, including one from the ISGlobal research institute in Barcelona.

An international team involving ISGlobal has analyzed climate data from 50 editions of the Tour de France between 1974 and 2023. The results show that, during the month of July, the risk of heat stress has increased over the years, with the last decade seeing the highest number of extreme heat episodes. In the locations analyzed, the Tour has so far managed to avoid conditions of maximum risk to health, but according to the researchers, it has been "an extremely fortunate race. With record heat waves becoming more frequent, it seems only a matter of time before the Tour faces days of extreme heat stress that will test current safety protocols. The study, published in Scientific Reports, used the Tour de France as an example of the challenge that rising temperatures associated with climate change pose for the organization of sporting events in the summer.

The inclusion of transgender women in women's sports categories is a controversial decision. To compare body composition and physical fitness between transgender and cisgender women, a team from Brazil has conducted a meta-analysis encompassing 52 studies and 6,485 individuals, analysing these values before and after gender-affirming hormone therapy. Although trans women showed greater lean mass—an indicator of muscle mass—there were no significant differences in upper or lower body strength, nor in maximum oxygen consumption, compared to cis women one to three years after hormone therapy. ‘The current evidence is, for the most part, of low certainty and heterogeneous quality, but it does not support theories about the inherent athletic advantages of trans women over cis women,’ say the authors of the study, published in the British Journal of Sports Medicine.

A study based on models and data concludes that adverse health effects related to plastic emissions could more than double by 2040 if current practices do not change. The authors note that their model could not assess the potential impacts associated with many chemicals contained in plastics, nor with the microplastics and nanoplastics that form throughout their life cycle, due to a lack of data and “a serious lack of transparency regarding their composition.” The results are published in The Lancet Planetary Health. 

A study published in Nature estimates that atmospheric microplastic emissions have been overestimated. The authors compared measurements of atmospheric microplastics from 76 studies conducted between 2014 and 2024 at various locations around the world with model simulations. According to the simulations, atmospheric microplastic concentrations were between 100 and 10,000 times lower than previously estimated.

Moderate-intensity physical activity, such as walking at an average speed of 5 km/h for an additional five minutes per day, is associated with a 10% reduction in all-cause mortality among most adults, according to a study published in The Lancet. The research also found that reducing sedentary time by 30 minutes per day was associated with an estimated 7% reduction in all-cause mortality if adopted by most adults. The study analyzed data from more than 135,000 adults from Norway, Sweden, the United States, and the United Kingdom, with an average follow-up of eight years.

One oral dose of zoliflodacin—a new antibiotic—is as effective as the current treatment for uncomplicated urogenital gonorrhoea, according to the results of a phase 3 clinical trial published in The Lancet. In some parts of the world, the bacteria that cause gonorrhoea have developed resistance to the current treatment, which combines an injection of ceftriaxone and an oral dose of azithromycin. Zoliflodacin could be an alternative to this treatment, concludes the study, which included 900 people from five countries.

Amino acids are the building blocks of proteins. These are known as the building blocks of life, but they cannot replicate themselves. To do so, they need the instructions provided by RNA. How this relationship began is still a mystery. Now, a British team has shown how it could have started from relatively simple conditions. According to the researchers, who published their findings in the journal Nature, ‘understanding the origin of protein synthesis is fundamental to understanding where life comes from.’

Analysis of data from a mobile health app covering more than 5,000 people in 1,609 cities in the United States reveals that moving from a less walkable area to a more walkable area leads to an increase in the number of steps taken per day, and vice versa. Walkability was measured using the Walk Score, an index based on parameters such as proximity to services, block length and intersection density. According to the authors, the results can serve as a guide for urban design policies that improve public health. The study is published in Nature.

Ahead of the anticipated conclusion of a United Nations global treaty on plastics, a group of international experts calls for greater attention to health effects when addressing plastic pollution. The work, published in The Lancet, reviews current evidence on how plastics—including microplastics and plastic chemicals—affect health, and announces the launch of a new project to monitor these effects.