Summer is almost here. What’s the best way to get fit in only a month?

Memorial Day is not too far off.

That means you have one month to get in shape before the unofficial start of summer.

It may not seem like much time, but don’t hang up your running shoes just yet.

“Shaping up in 30 days requires discipline, but it is possible,” Dempsey Marks, a fitness expert and creator of the PreGame Fit program, told Healthline.

So what does it take to get in shape in 30 days?

It depends on where you’re coming from.

“When working on a short-term goal of getting in shape, you have to know your starting point and your previous experience,” James Shapiro, a certified personal trainer with New York-based Primal Power, told Healthline.

Whether you are a beginner, a weekend warrior, or a long-time athlete will determine what training program works best for you. And how “fit” you can get in one month.

Read more: How long does it take to get in shape? »

If you are new to exercise, or coming off a long break, Shapiro suggests that you start with a cardiovascular program.

Run or jog 20 to 30 minutes every other day. You can also do other moderate-intensity activities like walking briskly, swimming, or bicycling.

After your cardio workout, do three to four sets of bodyweight exercises like squats, pushups, lunges, burpees, or Russian twists.

“You will need a day of rest between these kinds of days,” said Shapiro, “but you can stay active by taking up yoga to reduce stress, increase blood flow, and work on your flexibility.”

After that, slowly add in strength training. This will boost your metabolism and help burn more fat and calories.

If you have access to a gym, Shapiro suggests doing three to four sets of strength exercises, with 12 to 16 repetitions per set. This can include movements like chest presses, lat pulldowns, rows, and leg presses.

If you don’t have a gym nearby, a personal trainer can help you develop a strength program that you can do at home with bodyweight exercises, dumbbells, and kettlebells.

Read more: What exercises are the best? »

For fast results, Marks recommends full-body strengthening exercises and high-intensity interval training.

“This type of routine will improve aerobic capacity and build muscle so you accomplish two goals at once,” said Marks — sculpting your muscles and burning fat.

High-intensity interval training alternates vigorous exercise with moderate exercise or rest periods. This can give you good results even with shorter workouts.

Marks suggests aiming for three days a week of high-intensity interval training, with a day off in between.

It works like this: alternate 30 to 60 seconds of moderate exercise with 30 to 60 seconds of vigorous exercise. Repeat this cycle for 20 to 30 minutes.

Personal trainer and fitness instructor Ashley Pitt said this type of training can be done on a treadmill — she suggests one minute “all-out” sprints followed by two minutes of walking, for a total of 15 to 25 minutes.

“You could also do high-knee runs or burpee intervals if you don’t have a treadmill available,” Pitt, creator of the healthy lifestyle blog A Lady Goes West, told Healthline.

High-intensity interval training is used by athletes of all levels to take their fitness to the next level. With modification, it can even work for beginners.

“If you aren’t a runner or are just getting started in your fitness routine,” said Pitt, “you can do super intense power walking by swinging your arms and not holding onto the treadmill, and following the same interval pattern.”

For the vigorous part of the cycle, increase the walking speed or treadmill incline.

You can also do this training outside on a track or sidewalk, with hills or stairs serving as the incline.

Another short, but intense, workout is circuit training — a fast-paced mix of cardio and weights.

“The biggest factor in circuit training is the reduction of the rest period,” said Shapiro. “More volume of repetitions and a lowered rest interval results in an increase in performance.”

Read more: 5 workouts that give you the afterburn effect »

If you already exercise regularly, you might want to choose one thing to work on for the month.

Justin Fauci, a certified personal trainer and co-founder of Lean Muscle Project, suggests focusing on “a particular performance barrier that you haven’t quite been able to break through, and set a specific, measurable goal.”

This might mean bench pressing 10 pounds more than usual or shaving two minutes off your two-mile run time.

Once you have decided on a goal for the month, restructure your training program to get you there.

“This will make you much more focused when training,” said Fauci, “and you may find yourself reinvigorated by your exercise plan all over again because you have your sights set on a specific goal to be accomplished within a set time period.”

Advanced athletes or weightlifters — those who have been consistent for four or five years — “will not see tremendous strength gains within a month,” said Shapiro, “so focus on your volume of training rather than the intensity of the weight you’re pushing.”

Shapiro said this group can also benefit from movements that build power. For a cardio workout, try boxing instead of traditional activities like jogging or riding a bike.

You can also add plyometrics — explosive movements like box jumps and plyo pushups — to your workouts. Or incorporate other power movements such as using a push sled or prowler, or doing heavy tire flips.

Read more: 3 essential gluteus medius exercises »

The best way get results in one month is to be realistic about what you can accomplish.

One mistake that beginners make is setting a goal in terms of weight, not fitness, like “I will lose 5 pounds by Memorial Day.”

This can backfire.

“It’s very common for beginners to be able to build muscle and lose fat simultaneously,” said Fauci, “and after a full month of committing to a regular workout plan, end up being the same weight — even though they’re in significantly better shape than when they started.”

At the end of the month, this “failure” may discourage people from continuing to exercise.

Beginners may also expect too much from their workouts, like wanting to lose 20 pounds and have six-pack abs in a month.

Fauci suggests that beginners focus less on physical results early on and more on their behaviors.

Instead of setting a goal of “I will lose 5 pounds in 30 days,” try “I will do my best to complete four workouts each week for the next month.”

Shifting the focus like this, said Fauci, makes the goal more achievable — the only way to fail is to not even try. It also takes off some of the pressure to be perfect.

“The reason I particularly like these types of goals for beginners is that most new exercisers haven’t yet developed the habit of exercising,” said Fauci, “and building the habit is the first step to getting the kind of long-term fitness results that most people really want.”

Read more: Do 5-minute workouts really work? »

Fitness experts agree that the fuel you put into your body has a big effect on your level of fitness and your performance.

By itself, eating healthier can “radically change an individual’s body fat percentage and maintain lean body mass,” said Shapiro.

This means cutting out refined and fast foods, eating more fresh foods — especially fruits and vegetables — and finding a balance of nutrients.

“Just eliminating sodas, candy, and alcohol from your diet will flatten your stomach,” said Marks.

She also suggests that you aim to get 60 percent of your calories from carbohydrates, 20 percent from proteins, and 20 percent from fats.

And drink plenty of water.

“The more water, the better,” said Pitt. “Stay extra hydrated and your skin will look better, you will be less hungry, and you will even feel more flexible, as the water keeps your muscles and ligaments looser.”

You might even benefit from eating dinner earlier and not eating again until morning — putting the “fast” back into breakfast.

“By finishing up your eating by 7 p.m.,” said Pitt, “you will give your body a chance to reset each night, over a good night’s sleep, and you’ll wake up with a slimmer stomach.”

Part of the benefits come from cutting out the mindless late-night snacking in front of the TV. But eating dinner earlier will also get you to bed earlier.

“The best times to sleep each night are during darkness,” said Pitt, “so aim to be in bed by 10 p.m. and up around 6 a.m. with the sun.”

Whether you want to lose weight, get stronger, or boost your performance over the next month, there’s no better time to start than right now.

Thirty days will fly by, but if you stay focused, you can achieve big results.

“While it’s physically impossible to go from overweight and out of shape to looking like a Men’s Health cover model by Memorial Day,” said Fauci, “one month is definitely a reasonable amount of time to see clear results in terms of fitness.”