For whatever reason, there is this pervasive belief in the general public that cardio is for losing body fat.And lifting weights is for "toning". Or that fat can ONLY be lost through cardio, and that lifting weights is ONLY for gaining muscle.
All of these things are wrong.
To make a point-Fat loss is an outcome of an energy deficit. If you create one through eating less, you will lose fat.If you create one through EXERCISING, you will lose fat.That said, fully understanding this requires nuance.Calories In, Calories Out is thermodynamics, and yes that is always in effect, but HOW you create this matters immensely.The major issue with "cardio" for fat loss is that it does not change your actual metabolism/physiology. Yes, it creates a deficit and yes you can lose weight.
BUT YOU BUILD NO MUSCLE.
And even further, cardio can become catabolic, meaning your body starts eating itself.Especially if you don't eat enough protein. Less lean skeletal muscle mass = slower metabolism while at rest.Remember-muscle is the ultimate metabolic equalizer. The more you have the more calories you will burn at rest.
Women do this all the time-Cut calories -barely eat protein -try to RUN 4-6 days a weekAnd they lose weight, due to the thermodynamic equation. But they also lose what little muscle tissue they have.Its a NONSUSTAINABLE deficit. And it causes major rebound in FAT gain, because your body hates being starved and underfed.This ultimately leads to some form of thyroid issue.The ONLY way to alter how your body uses fat, stores fat, eats food, produces hormones, partitions nutrients,the ONLY way to dramatically change your central nervous system health, your thyroid, your brainthe ONLY way to permanently lose fat and never gain it back, is to build MUSCLE.
You MUST GAIN MUSCLE.
Muscle is a complex tissue that has a massive cascade effect across EVERY single system of the body, all of it.You cannot "diet" forever. The only way to restore your metabolism in dieting is with muscle.And the most effective way to diet is to do in controlled bursts, on a continuum, and to ALWAYS BE LIFTING WEIGHTS.Does cardio have benefits? Absolutely, it has many positive health effects especially done in addition to a soundly designed resistance training program.But cardio, traditional cardio, it hardly builds muscle.You can lift weights for cardio, and done with an appropriate diet, you will lose fat.Even better, in adding muscle tissue, you can actually elevate your metabolic rate over time, and the major shift in physiology can fix your body's "set point" body fat level down to a lower healthier body composition.If you do none of that though, and try to starve and "cardio the weight off", you are fighting a war with yourself.And biology is going to win, and you will wind up overly fat.
Be smart, lift weights.