Medical Bulletin 04/October/2025

To reach these findings, researchers monitored heart rates of individuals with varying fitness levels over a 24-hour period, including during training sessions. Even after accounting for exercise-induced heart rate spikes, the total daily beats were still lower in fitter individuals. Some athletes had resting heart rates as low as 40 bpm, compared to the typical 70–80 bpm seen in less active individuals.

“The fitter you are, the more metabolically efficient your body becomes,” said Professor André La Gerche, head of the HEART Laboratory. “Even if you’re training hard for an hour a day, your heart beats more slowly for the other 23 hours. The net effect is fewer beats used overall.”

Lower resting heart rate is not just a marker of fitness, but also of longevity and better cardiovascular health. While extreme endurance sports may temporarily increase daily heartbeats, the study found that regular, moderate exercise delivers the greatest benefits.

“The biggest bang for your health buck is going from unfit to moderately fit,” Professor La Gerche concluded. “Just a few hours of purposeful exercise each week can transform your heart’s efficiency and help make every beat count. It may even extend your life by years.”

Reference: Van Puyvelde, T, Janssens, K, Spencer, L. et al. Balancing Exercise Benefits Against Heartbeat Consumption in Elite Cyclists. JACC Adv. 2025 Oct, 4 (10_Part_2) https://doi.org/10.1016/j.jacadv.2025.102140

Mechanism for Regenerating Lost Tooth and Bone: Study Finds

In a recent study, researchers from the Institute of Science Tokyo (Science Tokyo) have identified two distinct stem cell lineages responsible for forming the tooth root and surrounding alveolar bone. Their discoveries, published in two related studies in Nature Communications reveal new insights into the cellular signaling and differentiation processes that underpin natural tooth development—paving the way for future stem-cell-based therapies.

Tooth loss has long been treated with artificial replacements like implants or dentures. While effective, these methods fall short of replicating the complexity, feel, and function of natural teeth. As a result, scientists have turned their attention to understanding how teeth form in order to unlock regenerative treatments. But tooth development is a highly coordinated process, involving multiple tissues and signaling pathways that remain only partially understood.

The research team studied the cellular dynamics at the growing tip of tooth roots in genetically modified mice. Using lineage-tracing techniques, fluorescent tagging, microscopy, and gene-silencing tools, they uncovered how specific populations of stem cells specialize into different tissues within the tooth and jaw.

One stem cell population, located in the apical papilla of the developing root, expresses the signaling protein CXCL12. These cells were found to differentiate into odontoblasts (tooth-forming), cementoblasts (root surface-forming), and osteoblasts (bone-forming) through the canonical Wnt signaling pathway. The second lineage, found in the dental follicle, consists of cells expressing parathyroid hormone-related protein (PTHrP), which can become cementoblasts, periodontal ligament fibroblasts, or osteoblasts—but only under specific conditions.

"We observed that the Hedgehog–Foxf pathway needs to be suppressed to drive the alveolar bone osteoblast fate of PTHrP-expressing cells in the dental follicle, unraveling a unique tooth-specific mechanism of bone formation requiring deliberate on–off regulation of Hedgehog signaling," said Assistant Professor Mizuki Nagata from the Department of Periodontology, Graduate School of Medical and Dental Sciences at Institute of Science Tokyo (Science Tokyo), Japan,

These findings offer a deeper understanding of how the root and supporting structures of teeth form naturally.

Reference: Mizuki Nagata et al, Wnt-directed CXCL12-expressing apical papilla progenitor cells drive tooth root formation, Nature Communications (2025). DOI: 10.1038/s41467-025-61048-x

Yoga vs. Exercise: Study Reveals Which One Really Boosts Vascular Health?

Yoga may be less effective than conventional forms of exercise when it comes to improving vascular health, according to a new systematic review published in Advances in Integrative Medicine.

The study is a comprehensive review of existing research, including randomized controlled trials, crossover trials, and non-randomized studies. Researchers focused on comparing the effects of yoga versus other forms of exercise in sedentary adults, specifically looking at vascular function—an essential marker of cardiovascular health. Using ultrasound-based assessments, the study evaluated how different types of physical activity influenced the elasticity and responsiveness of blood vessels.

Vascular function, often described as the ability of blood vessels to efficiently transport blood to tissues, plays a critical role in preventing hypertension, heart attacks, and strokes. Prolonged sitting and sedentary lifestyles are known to impair this function.

"Think of blood vessels like flexible garden hoses. If they stiffen, the risk of heart attacks and strokes increases," explains co-author Dr. Leena David, a medical imaging specialist and lecturer at the University of Sharjah. "Our study shows that structured exercise keeps those hoses flexible, while yoga provides some benefits but not as reliably. Middle-aged and older adults often notice improvements from yoga, but younger adults might not."

The research found that other forms of structured exercise—such as Tai Chi, Pilates, and high-intensity interval training—consistently outperformed yoga in improving vascular health among sedentary individuals. Dr. David emphasizes that “movement is essential,” but adds that “the type, intensity, and consistency of physical activity are key determinants of vascular health.”

“Even simple routines can make arteries more resilient. Blood vessels have a memory -- and every workout helps them forget the damage of sitting all day,” she notes. She describes prolonged sitting as "the new smoking -- silent, sneaky, and stealing years from your arteries," and encourages people to see movement as “the perfect antidote.”

The researchers advocate for physical activity to be viewed not just as a tool for weight loss, but as a proven strategy to improve vascular health.

Reference: Poovitha Shruthi Paramashiva, Suresh Sukumar, Dilip Shettigar, Rajagopal Kadavigere, Abhimanyu Pradhan, Nitika C. Panakkal, Winniecia Dkhar, K. Vaishali, Baskaran Chandrasekaran, Hari Prakash Palaniswamy, Sneha Ravichandran, Sathya Sabina Muthu, Koustubh Kamath, Haris Jose Felix, Anam Shazli, Leena R. David. Comparing the effects of yoga and exercise on vascular function: A systematic review. Advances in Integrative Medicine, 2025; 12 (4): 100556 DOI: 10.1016/j.aimed.2025.100556