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First, Be a Good Animal.

First, Be a Good Animal: The science and philosophy of aging well for adults 50+.

Strength, longevity, and the joy of moving like a good animal, from a 74-year-old trainer still in training.

This is a collection of articles written by Marty Trussell, NASM-CPT, Founder of VirtaFitness. Part science, part memoir, part philosophy, this is a blog for anyone who wants not just to slow the decline, but to keep building.

It all begins with a series called The Numbers Don’t Lie. Five of them, to be precise. Five instruments. Five readings on the panel of the life support system you have been running, without checking the gauges, for most of your adult life.

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Marty Trussell, NASM - CPT 10/21/26 Marty Trussell, NASM - CPT 10/21/26

HRV: Your Fitness Tracker Might Already Know This — But Do You Know What It Means?

Here’s something that may surprise you: if you wear a Garmin, an Apple Watch, a Whoop band, or an Oura Ring to bed at night, there is a very good chance your device has been quietly measuring this metric for months — possibly years — without you paying much attention to it.

It’s called Heart Rate Variability. HRV.

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