Every session should start with mobility, they say. Train intelligently, though, and mobility work is a patch for bad programming, not a requirement.

Running for performance and running for healthy joints call for different technique. How foot strike, stride and hip strength change the load on your knees and back.

Reading exercise biomechanics on a moving body is hard. So stop it. Freeze the top and bottom of the rep, and the forces become easy to see.

Most trainers should carry a logbook; a session without one can look like winging it. The exceptions are real, though, and load isn't the whole story.

The wriggle near failure is the easy way out. Teach a client to hold form to the edge instead, and spotting starts to make real sense.

Trainers should see efficiency through a different lens from sports coaches (and yes, CrossFit and Hyrox count as sports). It changes how you judge an exercise.

One viral clip can look like overnight success. The coaches who earn the lasting kind run a quieter loop most people never see.

Reading an exercise's biomechanics sounds complex. It isn't. A few simple checks reveal what any movement challenges, and how to build one for any muscle.

Teaching people to build muscle isn't a high-value skill. Almost anyone can do it. The real value of a trainer sits somewhere else entirely.