physiology

A new study reveals that aging changes the body’s walking strategy, prioritizing balance and safety over efficiency. Walking may seem automatic, but every step requires a complex balance between stability, muscle coordination, and forward propulsion. As people age, that balance begins to shift. New research from Australia suggests the body gradually adopts a more cautious [...]

Researchers have identified a potential biological signature of sleep loss in saliva, bringing scientists closer to an objective test for detecting dangerous fatigue. A driver who has been awake for an entire day can be as impaired as someone who is legally intoxicated. Yet unlike alcohol, there is no roadside test that can objectively determine [...]

Maximal oxygen uptake (VO₂max) is widely recognized as the preeminent measure of aerobic capacity and is typically assessed using graded exercise testing (GXT). This study examined the test–retest reliability of VO₂peak and associated physiological responses during a staged GXT performed on a combined upper- and lower-body air-braked ergometer. Fifteen recreationally active adults (9 males, 6 fem…

Nature, Published online: 20 May 2026; doi:10.1038/s41586-026-10564-x l-2-Hydroxyglutarate is identified as a legitimate physiological signalling metabolite, and control of its levels is essential for postnatal growth and survival and correct renal development and function.

The practice of freediving is teaching physiologists how humans stretch their physical and mental limits, which in turn may improve treatments for lung and heart ailments.

Fur seals may look relaxed on shore, but their hearts reveal a hidden battle still underway after deep dives. Diving places enormous physical stress on marine mammals. During long and deep dives, animals can switch to ‘anaerobic’ (oxygen-less) metabolism in parts of the body outside the heart and brain, which leads to a buildup of [...]

Cognitive pressure disrupts muscle control and blood flow, highlighting its role in physical performance during low-intensity motor activities.

Fur seals may look like they’re simply resting after exhausting hunting trips at sea, but their bodies are secretly working overtime. Scientists discovered that hours after returning to land, the seals’ heart rates suddenly surge — sometimes doubling — as they recover from the intense physical stress of deep diving. The findings suggest that seals postpone much of their recovery until they’re saf…

Researchers investigate how birth weight determines kidney function changes following prolonged physical activity in different environmental conditions.

Scientific Reports, Published online: 30 April 2026; doi:10.1038/s41598-026-49353-x The effect of eccentric exercise-induced delayed onset neck muscle soreness on force steadiness and the spatial distribution of neck extensor muscle activity

Men tend to have a higher ratio of muscle to fat, but women respond just as well to resistance training This is a common misconception, says Prof Leigh Breen, a muscle physiology specialist at the University of Leicester, though it’s easy to see where it comes from. Men typically have a higher ratio of muscle to fat than women, largely because of differences established during puberty, when testo…

Scientific Reports, Published online: 25 April 2026; doi:10.1038/s41598-026-49695-6 Melanopic equivalent daylight illuminance of 2 lx maintains and restores physiological and neurophysiological circadian rhythms in rats

Long-duration microgravity induces pronounced musculoskeletal (especially lower-limb) and systemic cardiovascular deconditioning. We evaluate a combined countermeasure, artificial gravity (AG) via a short-arm, constant-radius centrifuge, lower-body negative pressure (LBNP), and resistive exercise (RE), to mitigate physiological and structural deconditioning in spaceflight analogs.

Astronauts' grip strength is severely impacted by space travel, with significant safety risks highlighted by a new study.

In short bursts, this hormone can help you face your fears. But in the long run, too much of it can be unhealthy.

Maternal cardiac remodeling during pregnancy is a structured physiological process that supports increased circulatory demand while preserving functional stability and enabling postpartum recovery. This process can be described in terms of the interaction between intrinsic adaptive capacity and exposure load. Intrinsic adaptive capacity reflects the system’s ability to generate and sustain coordi…

Musculature, strength, size, and endurance are maintained only so long as they are demanded. The moment that demand disappears, the physiological mechanisms that once built muscle now work towards energy conservation, initiating a gradual, though measurable, decline