I'd been away from the gym for a decade until I started using this app. Now, I work out 4 times a week.

• I hadn't been to the gym since I was a high-school senior over a decade ago.
• I started using Fitbod, and now I feel motivated to go four times a week.

One of the best days of my life was June 14, 2012. I had just taken the last compulsory physical-education class of my life (in New York public schools, it's mandatory K - 12). I was king of the world.

Over a decade later, I wanted to get back into the habit of going to the gym, but finding motivation was tough. Building a workout routine from scratch is a headache and requires a lot of research.

A friend recommended I check out Fitbod to help build my routine, and it's completely changed my relationship with the gym.

Fitbod helps me set my fitness goals and stay on track with the right kinds of exercise

Fitbod is an app that lets you customize your workouts based on what you want to achieve. You can choose from a variety of goals — strength training, increasing muscle mass, powerlifting, and general fitness, to name a few.

You can also choose a level (I am still proudly at the beginner level a few weeks in), and Fitbod will start to pick up on your progress as you start to log what you're doing. Also fair warning: the first beginner workouts I got from Fitbod felt super challenging and of the five recommended exercises, I'd barely get through two. The more you log in the app, the more precise your workouts will be, I've found.

Fitbod tracks your muscle groups' recovery — so today, I focused on my back and lower back, meaning that tomorrow Fitbod knows to recommend other areas of my body to focus on. It also gives you brief demonstrations of how to do each exercise, though you should always ask a trainer in the gym if you feel you're unsure of how to do a workout without injury.

Fitbod requires some fine-tuning in order to get the most out of it

I do have two caveats for anyone using Fitbod.

First, the beginner level felt really out of reach for me when I started, so don't be afraid to adjust down. It's great to start slow and focus on easier workouts so you can get your form down and make sure you're doing everything the right way before amping up the difficulty.

The first exercises it recommended to me were well above my (truly novice) level. It gets a lot better when you've input enough data for it to adjust its recommendations, but those initial workouts were too tough.

Second, I highly recommend watching the demonstration videos, since the written instructions tend to be long and, at least for me, slightly confusing. They do have good tips on when to breathe, whether your knees should be slightly bent, etc., but the videos are much more helpful and user-friendly, in my experience.

Fitbod actually keeps me motivated to go to the gym because I have a clear game plan I can sort out the night before

The best part of Fitbod is figuring out the night before what you want to focus on and customizing the workout — adding a few reps here and there, swapping something out because you know a certain machine is usually unavailable, that sort of thing.

I now go to the gym four days a week, which was previously unthinkable. The ability to create focused workouts and customize them as little or as much as I see fit has been a total game changer.

Before using the app, I was struggling to figure out what to even do when I went to the gym. I'd often do a machine or two before just hopping on the treadmill because I wasn't sure what I should be doing. Now, I feel much more confident, which keeps me motivated to show up.