Marathon/ Half Marathon training fundamentals from a Personal Trainer’s perspective.

Carlos Anthony Castro
4 min readMar 30, 2023

I can remember a phone conversation with my mother back in early 2016. I was training for my first marathon at the time. I told her I’d never want to run another marathon after this. Just knowing the amount of preparation that goes into this and the mental toughness it would take. Welp! He we are 8 marathons later!

As the saying goes, marathon runners are either “1 and done” or “you’re one of us”. Aspiring half marathon runners, you all are equally awesome, yet a little more sane than us marathon runners( but here’s to you joining the club ).I’ve written a few runner related blogs in the past. So if you’ve heard my story you know I credit marathon running with giving me a new mindset, and understanding of my own capabilities. And the result is me transferring careers into personal training(EQUINOX on the Miracle Mile).

This last marathon brought some challenges as I’m a bit more focused on my development as a personal trainer, & my clients progress. So along with my training, I consider that I spend a lot more time on my feet these days. In my previous life I worked a desk job. Back then it was all about me. Marathon/ half marathon training is a full time job in itself. But these days it been taking a backseat to my development as a personal trainer.

Nonetheless, I went out there on March 19th, 2023, ran 26.2 miles and was there the next day for my first client at 5am.

All of the above is my credentials as to why I can even write a blog like this. So let’s talk about some marathon training fundamentals.

  • You’ve got to decide that you want to do this? Do you feel the jitters? You should!A half marathon and marathon course are respectively 13.1 miles and 26.2 miles(looooooong). If you’re second guessing yourself, think about it before you commit. As a more experienced marathon runner, I had to question myself before my most recent marathon. The jitters didn’t arrive until very close to race day. And in the back of my head I’d told myself if I don’t feel it, I won’t go out there.But they were there(Let’s gooooooo)
  • Listen to your body. In case you didn’t know, Moms are always right, and women are generally smarter than men. My mom told me I was training too hard for my first marathon. I waived off her advice and ignored the mild shin splints. Understand this, training injuries are a result of the cumulative body of training. And in case you haven’t heard, overtraining is real thing!( just so happen to experience said injuries. Mom was right). My first marathon was a struggle through injuries. But I managed. Don’t ignore the small pains, not to be confused with soreness. It’s ok to take a day off.
  • Start off slow. We should be running at a pace that we’re able to hold a conversation with someone that’s running with us.I know the elite marathon runners are crushing 5 minute miles and making it look easy. But for you and me that’s an all out sprint. Focus on running with even effort, not even splits. In other words, run with the same level of intensity on the steep hill as you would downhill.
  • Strength train!!! Yes take your running shoes off and come spend some time in the gym. Proper strength training creates a stronger runner while reducing risk of injury. Lots of runners report knee pain. To be clear, running is not bad for our knees. Most knee pain from running is a result of an issue from one of ther other 2 nearby joints(hip and ankle). But there’s nothing structurally wrong with ther knee joint. Running is a movement that starts at the hip. And the hip has muscles connecting from both the upper and lower body in all planes of motion. So all the muscles at the hip need to be strong! (Hire a personal trainer for more details here).
  • 1 mile at a time. As you start your training, just remember to focus on the mile that you’re in and relax. As marathon/ half marathon runners, we’re our only competition.Enjoy the fact that you had it in you to get to this point. You’re a rockstar!!!

More to it than this blog? Definitely ! For more, check out my earlier blogs on strength training for runners, and how to pick out a running shoes. Just know you got this! !



Carlos Anthony Castro

*Personal Trainer* Marathon Runner * Instagram @iron_endurance_training