Elite athletes are constantly pushing the boundaries of what humans can achieve, but it all starts with what they put into their bodies to provide the energy necessary for pushing the limit and achieving new heights.

But it's not all lean meats and leafy greens.

Professional players need food, and lots of it. And sometimes simple is best — simple carbohydrates, that is. Breads, pastas, rice, potatoes and cereals are all critical fuel for an athlete's muscles. In fact, Usain Bolt, the eight-time Olympic gold medalist who's widely regarded as the fastest man alive, famously ate an estimated 1,000 McDonald's chicken nuggets over 10 days during the 2008 Beijing Olympics.

Of course, fueling for exercise isn't just about carbs.

The human body is an energy machine, and top athletes require considerably more energy to achieve the best possible performances. So how does their nutrition intake differ from an average person? And how might we learn from these all-star athletes to take our own health and nutrition to the next level?

Monica Bearden, a registered dietitian and sports nutrition consultant at Houston Methodist, gives us insight into these questions and more.

Q: How do different elite athletes like swimmers, gymnasts, weightlifters and runners eat based on their sport's needs?

Bearden: Athletes, like everyone else, need to eat enough energy or calories to fuel their performance — whether they are swimming, vaulting, lifting or sprinting. Calories provide the necessary energy for the muscles to perform and provide power and endurance to finish strong.

It's the same for those who work out an hour a day then sit and do work all day. Everyone needs the right number of calories to stay fit and have the energy to perform, whatever their "performance" may be. The difference is that athletes need a lot more energy for their training and competing.

Q: How important is nutrition to an athlete's training?

Bearden: Extremely important. Without the right nutrition, athletes are at higher risk of injury and illness and may not have enough energy or strength to compete.

Q: How do pro athletes stay fueled throughout competitions?

Bearden: The best energy for athletes comes from carbohydrates, so their diets are typically higher in carbs. Carbs are efficiently turned into energy and are the energy storage for muscles, called muscle glycogen. The trick for athletes is to replenish muscle glycogen used during training, so there is plenty for competing.

(Related: Does Carb Loading Really Work? (& More Race Training Nutrition Questions, Answered)

For athletes, simpler (or refined) carbohydrates are quickly digested and are great prior to training and competing — while the more nutritious carbs, such as fruits, vegetables and legumes (beans, lentils and peas), are great for recovering afterwards. Whereas with most non-athletes, they would benefit from these high-fiber, high-nutrition carbs as their main source of energy, as they digest more slowly and provide more nutrients per calorie.

Protein is also important during recovery for muscle building and repair to help build strength and stamina.

(Related: Are Simple Carbs Always Bad? Are Complex Carbs Always Better?)

Q: How is a top athlete's diet different than regular folks' diets?

Bearden: "Regular" folks need the same nutrients as athletes, just in smaller amounts. Calorie intake needs to match the calories needed for daily activity and exercise.

Choosing higher fiber, more nutritious carbs is preferred to the lower fiber, more refined carbohydrates used by athletes for immediate energy. Also, the ratio of carbs to protein is different for those who are not as active.

(Related: High-Fiber Foods: How to Get More Fiber in Your Diet)

Q: Are dietary supplements helpful, or is food-based nutrition generally enough?

Bearden: This is a huge topic, but in short, food is preferred, and supplements are just that — they supplement what you cannot get in food or enough food depending on calories needed.

Q: What can people take away from these all-star athletes in terms of their own healthy habits?

Bearden: Athletes tend to perform at their best when they receive adequate sleep and make healthy food choices — not just daily exercise and training. A great way to keep the body at its best is choosing fresh and whole foods (foods that have not been processed) and decreasing ultra-processed foods.

(Related: How Ultra-Processed Foods Harm Your Health with Examples of What Counts)

Athletes are also very good at consuming the right number of calories to fuel their performance. It's the same for everyone — food intake and food choices should match their daily needs and performance goals.

For many, this means choosing nutrient-dense and high-fiber foods that provide the necessary energy for daily living. This may be in an office or teaching all day, then running after kiddos all evening.

Whatever the day requires, healthy choices in the right amounts provide what is needed to feel your best and to have enough energy to conquer the day (or competition).

From simply managing weight to competition day, what an athlete's plate looks like

Most people aren't looking to become the next Biles or Phelps, but many of us aspire to better our health. In collaboration with the University of Colorado's Sports Nutrition Graduate Program, the U.S. Olympic Committee's Food and Nutrition Services devised the Athlete's Plate®, a scientifically tested educational guide to ensure nutrition intake aligns with particular conditioning regimens, whether the goal is hard training, moderate exercise or easier workouts designed to maintain or help lose weight.