Summary: Humans likely have an upper critical temperature (UCT) between 104°F and 122°F (40°C and 50°C), according to researchers. According to their findings, hot and humid conditions increase the resting metabolic rate, an indicator of energy consumption, in humans.
In temperatures above the UCT, the team is currently examining how different individuals’ heart function is. A major concern as the world warms is our ability to adapt to less-than-ideal environments, and the goal of this study is to learn more about this.
In hot, humid conditions, there is a human upper critical temperature (UCT) that causes a rise in resting metabolic rate. This UCT is most likely between 104°F and 122°F.
According to the findings of this study, cardiovascular responses to heat vary significantly depending on age and level of physical fitness.
The discoveries contribute important information about the body’s flexibility to warm pressure in a warming world and could have suggestions in different fields, including medication, sports, work conditions, and global travel.
Source: Society for Experimental Biology Current research by Prof. Lewis Halsey and his group at the University of Roehampton, UK, has revealed that humans likely have an upper critical temperature (UCT) between 104°F and 122°F (40°C and 50°C).
This rise in metabolic energy costs at high temperatures is being investigated further.
Prof. Halsey and his team discovered that when people are in hot and humid conditions, their resting metabolic rate, which is a measure of how much energy the body uses to keep running, can be higher.
According to Prof. Halsey, “quite a lot of work has been done on the range of temperatures that different animal species prefer to live at in terms of their metabolic rates being minimal and thus their energy expenditure being low.” On the other hand, “eeriely,” there is much less information available for humans when it comes to the upper limits of our thermal neutral zone.
Understanding the temperatures at which human metabolic rates begin to increase, and how this shifts between individuals, can have suggestions for working circumstances, game, medication and worldwide travel.
Prof. Halsey adds, “This research provides fundamental knowledge about how we react to environments that are suboptimal and how ‘optimal’ differs between people with different characteristics.”
In addition, Prof. Halsey and his team are looking into how temperatures above the UCT affect heart function and how different factors, like age and fitness, affect heart health in different people.
Prof. Halsey continues, “We found some significant changes in heart function responses to heat between categories of people, the most novel being between the sexes.” That is, cardiovascular responses to heat vary significantly between men and women on average.
Using a cutting-edge echocardiograph, Prof. Halsey’s team measured detailed heart function. Working this unit in the heat was difficult!”, He continues, The kind of equipment that is typically found in research laboratories but not in hospitals.
The most recent results of these experiments, which are ongoing, will be discussed in Prof. Halsey’s presentation at the SEB conference.
“We are steadily developing a picture of how the body responds to heat stress, how adaptable it is, the limits of those adaptations, and, most importantly, how diverse individual responses are. This knowledge becomes increasingly valuable as the world warms, he adds.