Kai Brenner
Fitness Writer
Younger men into the gym, gains, and evidence-based supplementation
Kai Brenner covers strength, muscle and supplementation for the gym crowd that wants gains AND receipts. He brings the energy of the weight room and the rigor of the research desk, and calls out broscience wherever he finds it.
Latest articles
The Next GLP-1s: Dual Fatty-Acid Conjugates and Combo Therapies Push Past Semaglutide
Two 2025 preclinical studies hint at where this class is heading — longer-acting molecules, beta-cell-protective stacks, and the first real challengers to semaglutide's throne.
The GLP-1 Side-Effect File: New Signals on Surgery, Pancreatitis, and the Gallbladder
Semaglutide and tirzepatide are reshaping body composition for millions of lifters and dieters. A cluster of 2025 reports is starting to map what happens when these drugs collide with surgery, scopes, and scans.
Tirzepatide vs. the GLP-1 Field: What the Switching Data Actually Shows
Patients are shuffling between Ozempic, dulaglutide, and tirzepatide. A small case series and a new biosimilar trial offer the first grounded signals on how this class is fragmenting — and what switching really looks like.
Beyond Weight Loss: The Expanding Clinical Map of GLP-1s
New 2025 data suggests GLP-1 receptor agonists are doing more than shrinking waistlines — with signals across the brain, kidneys, and operating room. Here's what the evidence actually says.
GLP-1s Are Quietly Becoming the Most Versatile Drugs of the Decade
Beyond fat loss and blood sugar, GLP-1 receptor agonists are stacking evidence in failing hearts, rare obesity syndromes, Alzheimer's, and even bone. Here's what's real — and what's still hype.
Beyond Semaglutide: The Next Wave of GLP-1 Combos and Dual Agonists
Phase III data on IcoSema and fresh SURMOUNT analyses of tirzepatide are rewriting what 'best-in-class' looks like for metabolic and obesity care.
Beyond the Scale: GLP-1s Are Quietly Reshaping Brain, Kidney, and Joint Outcomes
The same peptide class everyone's whispering about in the locker room is showing up in neurology, nephrology, and orthopedic data. The signal looks real — but moderate, not miraculous.
The Combined-Modality Prescription: Why Cardio Plus Iron Is the Real Cheat Code
A new narrative review argues that stacking moderate-vigorous aerobic work with resistance training delivers cardiovascular gains neither modality hits alone. A parallel Spanish trial asks what to do when frailty rules out the barbell.