Lower Body Work Fundamentals

Carlos Anthony Castro
3 min readSep 23, 2023


Training legs became the top priority for me after my first marathon in 2016. As I incorporated more leg day workouts I became a stronger runner while logging less mileage. Funny enough, while adjusting to this new routine of training without changing my diet I actually began losing weight. Most people thought it was because I running more, while the opposite was true.

Eight marathons later, I’m a personal trainer at the young ol age of 43 with 5 years of personal training experience. My own training is performance based BUT( My clients:I want to lose weight, I want a tighter core, I want to look leaner etc). All these goals cross at one place in the gym, LEG DAY!!

My experience:”Bros”= leg day blows “ladies”( lets GOOOO leg day!!!)

Training legs from an overall health/ longevity purpose:

Our hip joint at the bone consist of our femur/ thigh and our pelvis. It’s a ball and socket joint that articulates with 40 total muscles (both upper an lower body), at the most proximal part of our body. As with any structures, the foundation must be strong and stable. And if it’s not, the next joint is likely to suffer. Lots of knee pain issues that aren’t a result of some form of blunt forced trauma are likely due to weakness at the hip, as one part of the human body(kinetic chain) will always impact the next).

The result amongst the general population is the assumption that we have “bad knees”, and ultimately move less. And when we move less, our blood doesn’t flow which means our heart isn’t pumping as much. And if we’re moving less our muscles atrophy (we lose em).

Ie: cardio is great , but strength train more. Muscle moves our bones. No muscle =no movement.

Strengthen the foundation first!

Keep reading!!

Training legs for weight loss, and lean tummy:


Carlos whats the best exercise to melt away stomach fat???

So lets take a step back here and talk about food/ calories. Regardless of the macronutrient (protein, carbs , fats) regardless if it’s healthy or not all calories are the same once they’re digested. Healthier foods have micronutrients which the body needs(vitamins/ minerals etc) whereas “junk foods” are empty calories. But once digested they’re all equal( as the Google definition says, a calorie is a unit of heat energy in the amount needed to raise one gram of water 1 degree Celsius). This is important to understand because as the first law of thermodynamics states, “Energy can neither be created or destroyed. “

Ie: we either use it or we store it away.

Soooo, most of us store fat either in our gut our our hips(usually men=-gut, women=hips. Sidebar, thats why women usually live longer than us).

Thats a result of food consumption/ calorie intake that we didn’t burn away through movement.

So why train legs to melt away stomach / hip fat?

The name of the game (if this is your goal) is ultimately calories in vs calories out. If we burn off more than we’re putting in we’ll ultimately lose weight. But theres a lot more to it. Sleep, stress, hydration and hormones ultimately contribute to the bottom line. But NOBODY is above the rules.

Training legs recruits our bodies biggest muscle fibers that use THE MOST ENERGY EXPENDITURE: ie training legs and lifting heavy ultimately burns more energy while stabilizing our deep core muscles.

The bottom line, train legs for our overall health, train legs to look good, feel good, and great out there and perform good! TRAIN FROM THE INSIDE OUT!



Carlos Anthony Castro

*Personal Trainer* Marathon Runner * Instagram @iron_endurance_training