When you're training for a Spartan race or intensifying your workout routine, food is the fuel you need to reach your goals. If you’re loading up on grease and sugar and skimping on protein, complex carbs, and fat, you’re not going to progress much. 

Yes, to eat like an athlete, you need fat on your plate — throughout the day, and certainly bookending your workouts — to stay satiated and keep your body functioning optimally. How much do you need? About 20-35% of your daily calories should come from fat. That’s around 45-75 grams of fat per day, if you’re consuming around 2,000 calories a day, according to Natalie Rizzo, MS, RD. 

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“When your training intensity and duration increases, you burn more calories," Rizzo says. "If you’re not trying to lose weight, you need to eat back those calories. While fats haven’t been proven to enhance performance, healthy fats are a crucial part of taking in calories overall and curbing hunger after a workout so you don’t overeat or crave junk food."

How Do Fats Satiate So Well?

“Fats take a long time to digest, so they stay with you,” Rizzo explains.

Because fats have 9 calories per gram (compared to 4 calories per gram in carbs and protein), they provide the calories you need to eat to maintain your weight. 

Not all fats are created equal, however, so don’t think you can down a double bacon cheeseburger with a side of cheesy fries for the same results. Excess saturated fat and trans fats are detrimental for your body or your training regimen, and they might cause weight gain over time, too. 

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And even when you’re eating good fats, timing is key. Because fats digest more slowly, you’ll want to eat any fat-laden meal or snack a couple of hours before a workout, so it’s not sitting in your stomach during sprints.

Here are the best and worst fats to eat to keep your performance and body composition optimal.

The 5 Best Fats to Eat During Training

1. Nuts

Nuts like almonds, pistachios, walnuts, and peanuts (although technically a legume) are all fair game.

“All nuts are good sources of healthy fats,” Rizzo says.

Fat from nuts is unsaturated and has been found to reduce inflammation, which can make training easier and improve recovery time. Eating nuts has also been associated with a lower risk of heart issues, research shows. 

“I like to have nut butter before a tough workout to keep me fueled,” she says.

Don’t go over one tablespoon, as excess fat before a session can make you feel weighed down, impairing your performance. Post-training, reach for walnuts. They have omega-3 fatty acids, which are anti-inflammatory, so toss them in Greek yogurt as a recovery snack.

2. Seeds

“Seeds like chia, flax, and hemp offer healthy omega-3s and are a great addition to smoothies, salads, or energy balls," Rizzo says. "They don’t have much taste, but they add texture and protein.”

You can also use them to bread chicken, fish, or steak, getting that crispness you’re looking for. Their inflammation-lowering properties help you train better, recover faster, and experience less muscle soreness. 

3. Avocado

Avocados are one of the only fruits that have monounsaturated fats, which reduce inflammation, better your heart, and fill you up without filling you out.

“Plus, they have nearly 20 vitamins and minerals, and beneficial phytonutrients,” Rizzo says. “Recover after a tough training session with avocado toast topped with an egg and you’ll get carbs, fat, and protein.”

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Avocados are also high in potassium, an electrolyte your body needs to recover well and repair torn muscles, making them a smart way to satisfy post-training hunger.

4. Olive Oil

“There’s a reason this heart-healthy oil is part of the Mediterranean Diet — it’s rich in unsaturated fat and great for you,” she says.

Drizzle it on your salad or on the veggies that you grill up. 

5. Salmon

Eating fish twice a week is recommended, and salmon should be at least one of those times. It’s rich in heart-healthy omega-3 fatty acids, and the fat helps you feel full, so you won’t reach for ice cream an hour after dinner. 

As an added bonus, salmon has much-needed Vitamin D, to build bone density and prevent fractures and injuries. (Not what you want before a race.)

The Worst Fats to Eat During Training

1. Bacon

What’s not to love? Well, a lot, unfortunately. This breakfast staple is loaded with saturated fat, which can contribute to heart disease if eaten in excess. It also has tons of sodium, leading to water retention, dehydration, and bloating.

“It will also weigh you down if you have it before a training session,” Rizzo adds.

Better to swap it for lean turkey sausage or grilled chicken. Plus, bacon often has nitrates and nitrites, which some studies suggest are unhealthy. If you need your occasional bacon fix, buy a brand that’s free of them. 

2. Packaged Desserts

“We think of packaged desserts as loaded with sugar — and they are — but many also contain trans fat, which is so bad for you that it’s banned in many restaurants,” Rizzo says.

Related: 6 Tips to Create a Perfect Day of Eating for Fat Loss

How do you know if your cake has it? Scan the ingredient for “partially hydrogenated oil,” which stands for trans fat. If you spot it, you can do better.

3. Butter

Butter is another mostly-saturated fat.

“Eating too much butter can be bad for your heart,” says Rizzo.

Be careful not to go overboard. No more than 5% of the calories in your diet should come from saturated fat. For a 2,000-calorie diet, that’s 11 grams of saturated fat per day, Rizzo says. One tablespoon of butter has 7 grams of saturated fat, so if you need butter on your table, stick with a shaving, not a pat.