The Most Common Fitness Mistakes, According to a Personal Trainer

by Alina Gonzalez

We all try our best to live healthfully and do right by ourselves, but sometimes we’re our own worst enemy. At the end of the day, most of us aren’t personal trainers, just well-meaning people, and the world of fitness can feel daunting. That’s why we brought in the big guns (literally) and reached out to personal trainer Dallas Jay. As an expert who trains dozens of regular folks trying to be their fittest, he’s seen it all and knows the areas that most often trip people up and derail their goals. Keep scrolling to discover the most common fitness mistakes he sees and how you can avoid them.


“One of the most common mistakes I see newcomers to the gym fall into is overanalyzing fitness,” says Jay. “For a small percentage of the world, changing lifelong habits may be easy, but for most of us, it doesn’t happen overnight. We all know the truth about how to be healthy and get in shape: work out and eat healthy, nutritious foods.”

Jay says that almost every new client he sees comes to him with “hundreds” of questions (which he appreciates and will answer), but the main point he wants to communicate is that as a beginner, it’s a mistake to make fitness (and overall well-being) too complicated for yourself. “If you cook your food, drink lots of water, and challenge yourself in your workouts, your body will improve. Don’t make it rocket science!” he says.

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“For example, with today’s trending ‘pop-up diets,’ a lot of people feel the need to add these to their workout regimen to lose weight. Some people will go from eating out every night, to a Paleo diet and eating no carbs one week, and a replacement shake diet the next week. This is the ultimate setup for failure,” he says. “Our brain is wired to decide what decisions are good or bad on our blood sugar levels. The lower the level, the more likely we are to give in to the things we shouldn’t. So if you go from having an unlimited amount of carbs one week to none the next, you’re not really giving yourself enough time to adjust to lower blood sugars, and you’ll be going back to your old ways by day two.”

If you do want to try the Paleo diet, Jay says to gradually eat fewer carbs each week over a four-week period, consuming 25% fewer carbs each week till the end of week four. “This will allow your body to adjust and not feel starved throughout the day, causing stress and headaches"—which are a guaranteed saboteur of a great workout.


The next most common mistake Jay sees clients make is letting impatience get the best of them. "If getting a perfect body was a fast, easy process, wouldn’t everyone be in shape? Many newcomers to fitness expect instant results (probably because of social media these days and seeing so many people with awesome bodies, not knowing these people have probably put in years of work to get there), and if they don’t see a change in the first month, they get bored and give up,” he says. “But why begin a fitness journey when you don’t plan on doing it for life? Even if you did see great results in a month and stopped going to the gym, it wouldn’t be long before you’re back to your old body. If things aren’t going the way you thought they would at first, don’t be discouraged,” he urges. “Because one month, three months, or however long it may be, that is a short time compared to the amount of years deep down that you would like to live a healthy lifestyle. The two don’t add up. Consistency, over time, is what gets long-lasting results.

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"One of the many reasons new clients come to me is because they’ve seen great results in the past, and then one day hit a plateau and haven’t seen changed since then. The problem here is getting overly repetitive,” says Jay. “Why do we work out? To get stronger. That’s exactly what’s happening every time you go the gym. Which is why people plateau so often. Because things become easy." 

The treadmill is a common example. "If you run two miles every day of the week, every time you run those two miles, you’re getting a little stronger, a little faster, and essentially making it a little easier on your body. Which also means, each time, your body won’t be working as hard, so you won’t be burning the same amount of calories in those two miles as you were before, which is maybe why you’re not dropping weight like you were the first month you started doing cardio. Keeping your body challenged is key to getting stronger and seeing consistently fast results until you’ve reached your goal,” says Jay.

“Adding density to your workouts is the solution to staying challenged,” he says. “In other words, instead of doing the normal two-mile run time after time, try adding an incline, increasing by a percent each week, or adding intervals with sprints and then returning back to your normal pace.”

Related: The Right to Bare Arms: 5 Sculpting Moves for Toned and Lean Arms

In terms of weights, if you’re lifting weights to get stronger and haven’t seen a difference, Jay says you should be consistently adding more weight to keep up the challenge, along with adding more sets and exercise variations. “Keeping your body guessing gets fast results.”

Meanwhile, if you’re lifting to tone and haven’t seen any results lately, here are Jay’s tips: “Shorten your rest breaks between sets each week, until you have no rest breaks and are working out 45 minutes to one hour straight. At most you should be resting for one minute between sets. With each set of exercise, you should be doing at least three different exercises. For example, a back exercise, arms exercise, and abs exercise, then rest for one minute (max). The more you keep moving, the more your heart is beating, the more you’re burning fat!”

For more fitness tips, follow @DallasJay on Instagram!

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