When we lift weights or do resistance exercises, our muscles adapt by changing which genes are turned on or off. These genetic changes (called transcriptional changes) help muscles grow stronger and improve their metabolism. Both young and older people experience these changes, but aging changes how muscles respond at the genetic level, which may help explain why older adults don’t gain muscle as easily as younger individuals. In a study […]
Have you ever experienced muscle fatigue? You know the feeling where your muscles start to burn and no matter how hard you try, you simply cannot summon any more strength? It is often assumed that the burning sensation associated with muscle fatigue is due to lactic acid building up in the muscles. But is that the full story? In this time machine post, we examine the science behind muscle fatigue […]
Happy Pigeon Appreciation Day! Okay, I know it sounds strange to celebrate pigeons – the animal best known for gathering in large numbers, causing a raucous, as well as perching and pooping on just about everything. For just a moment though, I would like to consider the unique athletic attributes of these popcorn and park loving birds vs humans engaged in endurance exercise. Have you ever heard of pigeon racing […]
In todays’ Time Machine, we are taking a look back at a paper written by Dr. Henry Gray Barbour during his time in the Department of Pharmacology at Yale University School of Medicine. Published in Physiological Reviews in 1921, his paper examined how body heat is regulated in various species. In this review, Dr. Barbour explains that water is the best medium for conducting heat throughout the body. This is […]
Hibernation was also a hot…I mean warm…topic at the American Physiology Summit last month in Baltimore, MD. Thomas Crippen presented research conducted with team members Dr. Dylan Barth, Zac Carlson, Dr. Frank van Breukelen, and Dr. Allyson Hindle at the University of Nevada, Las Vegas. Their study focused on golden-mantled ground squirrels, Callospermophilus lateralis, which are remarkable even among hibernators. These squirrels can enter torpor across a range of environmental […]
We are very excited to share this winning guest blog post from Amy Klink, doctoral student at the University of Nevada – Las Vegas. Amy received the Dr. Dolittle travel award to present this research at the 2025 American Physiology Summit in Baltimore. Congratulations Amy! As a kid growing up in Lake County, Illinois, I spent more than half of my summer in some lake or body of water competing […]
Heat is a major physiological stressor that can damage proteins in the body, promote dehydration and even lead to death. Organisms living in hot environments must develop both behavioral and physiological mechanisms to prevent heat-related damage or illness. A recent review published in Physiology examined how humans and experimental animals adapt to heat (Laitano et al., 2025). Organisms that tolerate heat effectively can maintain normal physiological functions even when […]
Among mammals, humans are known for having exceptional endurance. For example, persistence hunters can run for 2-5 hours to wear out their prey, while marathoners routinely run ~4.5 hours on average (Schulte et al., 2015). Sure, a cheetah can run fast, but it can’t run as long as a human. How did humans develop such exceptional endurance? When vertebrates moved to dry land, they needed to develop lungs to extract […]
In this Time Machine post, we travel back to 1938 to check out a manuscript on the importance of amino acids in nutrition authored by Dr. William Cumming Rose (1887-1985), professor of biochemistry at the University of Illinois, published in Physiological Reviews. His research on the importance of amino acids in the physiology of an organism culminated in 124 research, review or biographical articles and his receipt of the National […]
The California Society of Physiologists is hosting their annual meeting today at the University of California Davis campus! Adapting to high altitude The keynote address will be given this evening by Dr. Tatum Simonson (Associate Professor, University of California San Diego) who will speak about, “Variation in human responses to low oxygen: Insights from Mount Everest to Machu Picchu.” Together with Dr. Francisco Villafuerte (Universidad Peruana Cayetano Heredia, Lima, Peru) […]
Life Lines by Dr. Dolittle 