Jack LaLanne (born Francois Henri LaLanne, and later nicknamed Jack), the “Godfather of Fitness”, was likely the first to coin & describe this concept several decades ago. It’s very simple and does make a whole lot of sense. Let’s explore what even the most astute personal trainers & athletes sometimes overlook.

The idea is that regular weight training assists with building muscle over time — and that it also helps in regards to fat loss (but in this example, it’s not simultaneous). The uncommon denominator, though, is that, while the training may be identical for two people, this discrepancy occurs for different body types.

More specifically, an ectomorph (i.e., a skinny person) will develop their musculature. An endomorph (i.e., a person with a relatively high percentage of body fat), on the other hand, will lean down.

How Does it Happen?

There are very logical explanations for why this may be the case. As far as ectomorphs are concerned, it’s more obvious. Tears in the muscle fibers from repeated weight training result in the build-up of scar tissue, which ultimately leads to larger (thicker) muscle fibers… or, in other words, muscular hypertrophy. As long as the test subject follows a balanced nutritional regimen consisting mostly of protein-dense foods (exceeding the amount of calories they’ve burned AND allowing for anything above the muscle recovery threshold), they’ll essentially get bigger.

Endomorphs primarily losing fat (not to mention improving their overall level of fitness) due to consistent weight/strength training is more debatable. That being said, I’d argue that it’s warranted. Why? Simply put, if you’re burning more calories than you otherwise would without the newly-established weight training routine, you should, in theory, get leaner.

Losing weight, however, brings in more challenges… because… as a reminder, you’ll likely be building up your muscles as well (given you’re not overtraining, or, as mentioned above, ingesting enough protein to sustain [past recovery] the recent changes in exercise).

Still, and particularly for individuals falling within an obesity spectrum, a weekly integration of weight training (especially during earlier periods) will almost surely result in both fat loss and general weight loss.

So, Is Weight Training an Equalizer?

Once again, and given my observations of now over 25 years of weight training (as well as over 20 years as a fitness professional), I’d say yes… definitely. A bigger question: Can you build muscle and lean down during the same time frame, meaning, at the same time (while either gaining or losing weight)? Answer: Yup… but that’s the subject of another article, actually several articles, many of which are already covered on this site!