Muscle Loss, Testosterone and How Much Strength We Can Regain with Dr Oskar Wenbar

Why do we lose muscle as we age, and how much can we rebuild, even in our seventies? For Dr Oskar Wenbar, the interest began after a stroke left his father bedridden. Watching his father’s physical condition deteriorate and his confidence disappear drew him into research on ageing muscle. In this episode, we look at what changes inside our muscles as we age, why it matters far beyond strength, and how much can be regained. We then move into more contested territory: testosterone replacement therapy and hormone optimisation, the muscle people may lose on GLP-1 weight-loss drugs, peptides, NMN, and whether biological-age tests tell us anything useful. Where is there good evidence to act, and where are we getting ahead of it? About the guest Dr Oskar Wenbar is a UK-based pharmacist and researcher whose PhD work at the University of East Anglia focused on skeletal muscle ageing. Born in Poland and raised in Chicago, he studied pharmacy in England and worked as a hospital pharmacist before moving into research. He is a co-founder of Evaro, a digital healthcare company that has served more than two million patients across the UK through online consultations and prescription treatments. Links and resources Evaro Evaro bios Dr Oskar Wenbar on LinkedIn Tasso 00:00 Welcome and Guest Intro 01:45 Oscar’s Journey to Longevity 05:42 Inside Ageing Muscle 08:49 Satellite Cells Explained 11:39 Why Muscle Loss Matters 15:33 Can You Rebuild Muscle 16:30 Training and Protein Uptake 19:47 Fast Twitch Fibres and Falls 20:54 DHT Testosterone and Muscle 23:08 From Mice to Human Evidence 24:43 Testosterone Decline Basics 27:06 Deficiency vs Optimization Debate 29:41 Stigma and Safety Evidence 31:02 UK vs US Testosterone Culture 33:54 Muscle Response and GLP-1 Risks 36:05 Peptides Hype Explained 38:12 NMN and NAD Boosters 39:36 Biological Age and Blood Testing 40:48 Needle-Free Blood Draw Devices 43:34 Longevity Basics and Essential Labs 45:51 Rapid Fire and Final Takeaways