We've heard it countless times before: Exercise is one of the best things you can do for your health. Working out regularly not only helps you maintain a healthy body weight (reducing the risk of chronic disease in the process) but research shows it can also improve energy levels, mood, mobility, longevity, sleep quality and immunity too.

However, finding the time to workout amidst the business of life? Not so easy to do. Whether it's been a couple months or a couple years, if you've fallen off your workout routine, don't fret! You can always begin again.

Read on for the advice from three fitness experts to learn how to start exercising safely. Equipped with knowledge from the pros, you'll feel more empowered starting a workout routine — no matter what level you're at.

How to Start Exercising

1. Prep your muscles and joints.

One of the most important parts of starting a workout routine is the prep. Before any workout, it's important to get your body warmed up. If you're looking to start running, heed this advice from Jeremy James, DC, CSCS, creator of Fit Forever: Give some extra attention to your muscles and joints before you start pounding the pavement. Mobility and strength in the ankle, knee and hip joints are crucial to successful running, he explains. But because these exercises can feel boring, many people skip them, leading to unnecessary injuries.

Luckily, it doesn’t take much to warm up. James suggests doing some on-the-ground exercises to activate your glutes, such as clam shells and bridges, as well as full-body exercises such as squats, split squats, lunges, lateral lunges and planks. Aim for 15 minutes of this type of strength work before any run. "The goal is to move your body in multiple directions," he says.

2. Progress slowly.

“The most common mistake new runners tend to make is increase their mileage too quickly,” says physical therapist and certified running coach Dylann Craig, DPT. A general rule of thumb: Increase your number of weekly miles by approximately 10 percent. This will significantly reduce joint strain and limit the onset of overuse injuries, such as shin splints or plantar fasciitis, he explains.

But this rule doesn't just apply to running. The same thing goes for weight lifting and strength training — you don't want to take on too much weight too soon or you can injure yourself.

3. Take some breaks.

"The run-walk method is a great way for runners to increase their mileage safely and improve overall cardio capacity," Craig notes. Adds James: The key here is to gradually increase the length and intensity of the running intervals, and not fall into the trap of walking simply because you feel like it, which would lead to a plateau in progress.

If you are new to running, look for a guided, beginner-friendly running program on an app, such as Nike Run Club or Variis, that can help you progress safely and effectively.

4. Don't skip the warm-up or cool-down.

Research shows that dynamic warm-ups are always best, Craig says. Think: jumping jacks, high knees or anything that gets blood flowing to the lower extremities.

"Cooling down is also important to ensure a gradual transition from an active state to resting state," explains Craig. This may include slowing down the intensity of a run for about five minutes, doing some static stretching and/or foam rolling. (Note: You want to avoid foam rolling prior to a workout, as it may reduce athletic performance, advises Craig.)

5. Move efficiently

This tip is for those wanting to amp up their running routine. Aim to land softly on the middle portion of the foot known as the midfoot or midsole, with the foot landing directly underneath the body, Craig recommends. "Running and striking with your heel first and out in front of you can slow you down and reduce your overall running efficiency."

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6. Establish your baseline.

“Most people will experience a decrease in strength and endurance after a long break, though it will vary based on how much training they have been able to do,” says Craig. When starting a workout routine after time off, Craig recommends treating your first strength-training workout as a test to see what your baseline is. After establishing this baseline, slowly begin to increase the number of repetitions, number of sets and add weight gradually as your strength comes back.

7. Start low.

If you're getting back into strength training, aim to start with around 50 percent of what you were lifting prior, in order to reduce injury risk, says Craig. Around 30 percent should also be safe, while yielding a more challenging and effective workout.

"Most importantly, give yourself some grace!" adds Hannah Davis, CSCS, CPT, founder of Body by Hannah. "It’s really important that you not get frustrated with yourself for feeling out of shape or realizing you lost strength and can’t do everything you could prior to taking a break. Enjoy the journey of building back up!"

8. Split up your training days.

Another important tip when starting a workout routine: split up your area of focus. "I recommend aiming for three to five days a week for strength training, with workouts divided into different body areas, known as splits," Craig says. A typical split may look something like this:

Day 1: Legs/Core
Day 2: Chest
Day 3: Back/Core
Day 4: Rest
Day 5: Shoulders/Core
Day 6: Arms
Day 7: Rest

This is a very general outline, and a mobility routine should be included at least three days of the week, Craig notes. He also recommends getting a sports medicine evaluation or consulting a fitness professional to make sure your training schedule matches your goals.

9. Watch out for red flags.

"No one wants to be so sore they can barely move for a week," Davis reminds us. That's why you want to watch out for DOMS (a.k.a. delayed onset muscle soreness), which begins 24 to 48 hours after a workout and lasts for three to five days. DOMS is an indication you are training too hard, too quickly, Craig notes. "This is the body's way of telling you to back off and reduce the intensity of that specific exercise."

Another red flag: Having difficulty maintaining correct form throughout a set. This can indicate muscle fatigue and if you are resorting to compensatory movement patterns, that can lead to injury, Craig says.

10. Don't discount bodyweight exercises.

"I highly recommend bodyweight exercises," Davis says. "They can be just as effective for building muscle as weight training!" You do need to progress the difficulty of bodyweight exercises over time as you master them to keep gaining strength, she notes. Either consult with a trainer or do the research on your own to better understand how to progress your exercise program.

Below, Davis shares five of her favorite bodyweight moves. For a balanced, full-body workout you can do anywhere, perform 10 to 15 reps of each for a total of three rounds:

• Overhead Squats: This exercise helps you improve your mobility and it’s also a surprising way to strengthen your back.
• Push-Up Alternating with Four Mountain Climbers: Modify if necessary by starting on a countertop and progressing by finding lower surfaces until you reach the floor.
• Reverse Lunge: This moves requires little space and you can always hold on to something for balance or assist until you feel stronger.
• Elbow Plank T-Spine Rotation with Hip Dip: This exercise is a great way to strengthen your shoulders and upper back as well as your core.
• Superman: Another great posterior chain exercise to strengthen the back!