Dave Bautista’s Kratos Rebuild: What Two Months Can Change
Dave Bautista says he is three weeks into weight training for Kratos with two months to go. Here is what experience and muscle memory can really change.
Chris Pruitt
Chris Pruitt is a certified ASFA personal trainer and the founder of WorkoutHealthy, a fitness equipment retailer serving customers since 2007. He has more than 16 years in the fitness business, and he writes and fact checks everything published on Insider.
How Dwayne Johnson Lost 50 Pounds Without a Crash Cut
Dwayne Johnson says he lost 50 pounds over a full year for Lizard Music. Here is what his slow cut can teach about pace, performance, and recovery.
The Hip Drill Fighters and Dancers Swear By
Fighters and dancers train the shin box, or 90/90 position, on purpose. Here is what hip rotation research actually supports about this uncommon drill.
How a 6 Second Hold Can Build Serious Tendon Strength
A 12-week study measured what maximal isometric holds actually do to tendon stiffness and strength. Here is what the real research behind "overcoming isometrics" shows.
Can a One Minute Wall Sit Really Work Like Cardio?
A wall sit does more than tire your legs. Here is what a 270-trial analysis found about isometric holds and blood pressure, and how to do one safely.
The 30 Day Experiment That Made Muscle Grow 4 Times Faster
A viral fitness experiment found that training a muscle daily made it grow up to four times faster on MRI scans. Here is what the experiment actually tested, and what it does not prove.
One Mile Every 4:48, Thirteen Times Straight: The Half Marathon World Record
Letesenbet Gidey ran 1:02:52 for the half marathon in Valencia in 2021, a world record that still stands nearly five years later. Here is what running economy, altitude training, and pacing science say about how she did it, and the real difference between a mixed-race world record and a women-only best.
114 Pounds, Two Rings, One Rep: The Science of the World’s Heaviest Ring Muscle-Up
Roudy Kallas added 51.86 kilograms to a ring muscle-up, a Guinness World Record. Here is the real biomechanics and strength science behind how that is even possible, and how to train toward weighted calisthenics safely.
Too Tall to Sprint: The Physics Behind Bolt’s 9.58-Second World Record
Usain Bolt's 9.58 second 100m world record has stood since 2009, verified directly against World Athletics. Here is what sprint biomechanics research actually says about his height, stride length, and the ground force behind the fastest 100 meters ever run.
The Bar That Bends: Hafthor Bjornsson’s Elephant Bar Deadlift Record
In 2019, Hafthor Bjornsson pulled 474.5 kilograms on strongman's whippy elephant bar, a record separate from his famous 501-kilogram pull. Here's what actually happened, and whether it still stands.