If you want to see your abs—really see your abs, not just slight definition—you need to zero in on what you're putting into your body. Most people focus on finding a nutrition plan that works and stick to it religiously, if not a little obsessively, until it stops working. 

But your body needs a wake-up call every once in a while. It needs to be challenged and catered to, just like your muscles. You don’t do the same workout every day and expect constant progress (and if you do, consider this your wake-up call to change that up, too.) Aside from a solid eating routine, you'll need a fresh workout routine too.

1. The staples

Animal foods are the best sources of protein because they contain all the amino acids the body needs to perform all its functions, including building muscle. Chicken, fish, eggs, lean beef, and turkey should be your dietary staples. Protein powder supplements are also an acceptable source. 

Remember that the fats in your diet will come mainly by way of your protein foods, but you can have fattier fare such as avocados, nuts, nut butter, and cooking oils such as olive and coconut to make up the rest.

2. Fuel up before and after

If you're looking to get lean, your pre- and post-workout meals need to be suited to your needs, however, some experts admit there is a bit of trial and error in order to perfect workout nutrition. 

We highly recommend a carb and protein shake (with approximately two grams of carbs for every one gram of protein) immediately after your last rep and a protein and carb meal (such as chicken breast and sweet potato) 60 to 90 minutes after the shake. And while some are a big believers of including a variety of fats in your diet, try to keep them out of the workout window as they slow down digestion—it's not something you want around the workout when you’re trying to build muscle and get lean.

3. Be careful with carbs

Strict low-carb diets reduce your ability to replenish muscle glycogen (the fuel stored inside muscle cells) which can make building and maintaining muscle a challenge. And since muscle is metabolically active tissue that requires constant energy to build and maintain, you want to build and keep as much of it as possible as it will contribute greatly to your fat-loss goals. 

The bulk of your carbs should come from foods such as potatoes, brown rice, pasta and vegetables. Most green veggies are very low in calories and may actually result in a negative calorie balance, since they can burn more calories during digestion than they contain. As a rule, you shouldn't eat more than two or three grams of carbs per pound of body weight.

4. Eat frequently

Many people still consume most of their food in two or three large meals every day, often going for hours at a time eating nothing in between. Sure, you can lose weight, and fat, on a reduced-calorie trio of meals, but you can't train your body to burn fat efficiently, which is key to maintaining weight loss.

A nutritious meal or snack every three hours or so stabilizes your blood-sugar levels, ensures adequate nutrients are constantly on hand, and helps control hunger-induced cravings for sweets and fats. It also leads to more effective glycogen storage in the liver and muscle tissues; thus, your body won't cannibalize muscle as an energy source during training.

So break your meals in half and spread them out. If you have trouble fitting in extra eating times at work, prepare food ahead of time that you can zap in the microwave or eat cold.

5. Do some math

But for someone who's active in sports and trains regularly, adequate protein is essential for gaining muscle and losing fat. Your safest bet is to ingest between 0.8 and 1 gram of protein per pound of lean mass.

When doing that calculation, use the weight you think you would look good at, especially if you're 20 or more pounds too heavy. For example, if an optimal weight for you would be 170 pounds, multiply that number by 0.8 grams: Your daily protein requirement turns out to be 136 grams, which translates to 27 grams of protein per meal (at five meals per day). That's about four slices of turkey breast deli meat or one small can of water-packed tuna.

6. Drink more

Fat is mobilized through a process called hydrolysis, and insufficient liquids in your body will hinder fat breakdown. Drink often throughout the day, and especially before and during a training session. Try to get at least 10 cups of water per day, although up to a gallon is okay. The main thing to remember is the human body is a bit out of sync: By the time it tells you it needs nutrients, it's already deficient. Never wait until you're thirsty.

7. Start heavy, end light

Your first meal of the day and your first post-training meal should contain your largest carb intakes of the day. Your body's glycogen stores are depleted when you wake up; promptly replenishing them is crucial to physical and mental functioning.

And your last meal (or two) of the day should emphasize protein, rather than slow-burning carbs such as potatoes and pasta. The carbs you do ingest should be the "wet" kind contained in high-water, medium-fiber foods such as cucumbers, leafy green salads, tomatoes and steamed asparagus. High-fiber, low-water foods absorb a tremendous amount of water, leaching it out of your system; since you can't drink while you sleep, wet carbs allow you to maintain relatively adequate levels of water during the night.

Bonus tip: Get in the habit of eating fish during your last repast of the day. Fish makes for a lighter meal, and it's a good way to replenish aminos while getting essential fatty acids. Fish is healthy as well: The American Heart Association recommends at least two servings of fatty fish (such as salmon and tuna) per week.

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