You may charge into the day full of energy, but by mid-afternoon, a wave of sleepiness hits you. You find it hard to keep your eyes open, or you find yourself yawning. Many people experience these late-in-the-day energy lags, but you can take steps to prevent them. Here are suggestions for healthy ways to keep your energy flowing throughout the day.

Don’t miss breakfast

The best way to keep your energy level at peak performance is to start the day with breakfast. Skipping any meal affects your concentration, making it more difficult to solve problems. And missed meals mean you miss out on nutrients. Often, people who skip meals end up overeating later.

Pick high-energy carbs

For a quick burst of fuel, choose foods high in complex carbohydrates. These are healthful sources of energy that digest the quickest. Go for whole-grain breads and cereals, hummus, fresh fruits, vegetables and vegetable sticks, pasta, and rice—even spring rolls or burritos. To hold hunger longer at bay, choose protein foods that take longer to digest, such as peanut butter or cheese.

Snack wisely

Instead of looking at snacks as extras, treat them as mini-meals that contribute to the overall nutrition for the day. Snack on fruits and vegetables to boost your intake of vitamins, minerals, and fiber; choose plain nonfat yogurt or café lattes made with skim milk to provide protein and calcium. When you snack, keep variety, moderation, and balance in mind.

Choose low-fat

Fat takes a long time to digest and makes the body feel sluggish. Most junk food is high in fat and/or sugar. Instead of buying chips or cookies from a vending machine at work, plan ahead and bring healthy foods for snacks.

Don’t overdo on sugar

Eating sugar causes your blood sugar to rise rapidly, which can result in an energy boost. But when sugar is introduced into the bloodstream, the body also produces insulin, which lowers blood sugar levels. Sometimes the body over-adjusts itself, causing the blood sugar level to drop rapidly, which explains the drop in energy some people experience about 30 minutes after eating a sugary snack. Sugar in moderation, particularly from fruit or juice, will give you energy without a lag.

Sleep well

Getting even an hour less of sleep can result in slower mental functioning the next day. Your reactions will be slowed and your memory may suffer. The average person needs—but doesn’t get—about seven to nine hours of sleep a night, according to the National Sleep Foundation.

Tank up on fluids

Your body needs a certain amount of water to function. When you don’t have enough water, everything slows down and becomes less efficient. Water is best, but other liquids, such as milk, juice, or the water in solid foods, will also work.

Get a caffeine boost

Caffeine is a stimulant, so it will give you a temporary energy boost. As long as you keep your caffeine intake moderate—about the equivalent of two to three cups of coffee (200 to 300 mg of caffeine) a day—caffeine doesn’t do any harm to most healthy adults.

Cultivate an active life

Exercise increases your endurance and makes your cardiovascular system more efficient, which gives you more energy for doing simple daily tasks. Exercise also helps you sleep better, improves your mood, relieves stress, helps with weight control, strengthens bones and muscles, and lowers your risk for a host of diseases. Be sure to check with your health care provider before beginning an exercise program.

Break for fitness

A good way to fight off fatigue during that afternoon energy lag is to do some stretches or take a quick walk around the building or parking lot. It will get the blood flowing. It’s also forcing your senses to become sharper and more focused.