Start typing, “Why am I…” in Google, and the search engine will auto-fill with the most popular query: “Why am I… so tired?” Clearly, it’s a question many people are asking themselves every day. In fact, one study found that nearly 40 percent of Americans wake up most days of the week feeling tired.

But sometimes a different question arises—especially when you’re dozing off at your desk in the middle of the afternoon or hitting snooze five times instead of going for a run. Sound familiar? You’ve probably also found yourself wondering, “Am I really tired or just lazy?

Turns out, both are a very real possibility. Mental fatigue and physical fatigue are completely different, says Kevin Gilliland, Psy.D., a clinical psychologist and executive director of Innovation 360 in Dallas. However, both play into each other and can affect each other. Here’s how to tell if you’re truly exhausted or just unmotivated—and what to do about it.

Signs You’re Actually Exhausted

The culprits behind physical exhaustion are typically either overtraining or lack of sleep.

Symptoms of overtraining include an increased resting heart rate, muscle aches that don’t dissipate within 48 to 72 hours after a workout, headaches, and decreased appetite (as opposed to an increased appetite, which usually occurs with increased physical activity), according to Traxler. If you notice any of these signs, take a couple of days off for rest and recovery.

The other main reason is sleep deprivation—which is a much more common cause, Traxler said. “You may not be sleeping enough hours or your quality of sleep is poor,” she explained.

Still tired even after you’ve been in bed for eight or more hours? That’s a sign you’re not sleeping well, Traxler said. Another clue: You wake up feeling rested after a “good” night’s sleep, but then at 2 or 3 p.m., you hit a wall. (One side note: Hitting a lull at 2 or 3 p.m. is completely normal, due to our natural circadian rhythms, Traxler noted. Hitting a wall that makes you feel completely fatigued is not.)

Causes of poor-quality sleep can range from stress and hormones to thyroid or adrenal issues, Traxler said. If you suspect you’re not sleeping well, the next step is to see your primary care physician or endocrinologist.

“Seek an M.D. who’s also a naturopath or functional medicine expert, so they can take a look more deeply into your bloodwork, nutrition, and stress levels to figure out what’s going on,” Traxler suggested.

In the Ayurvedic tradition (the traditional, holistic Hindu system of medicine), physical exhaustion is known as a vata imbalance. “When vata rises, the body and mind become weak and exhaustion sets in,” noted Caroline Klebl, Ph.D., a certified yoga teacher and an expert in Ayurveda. According to Ayurveda, this can arise from overactivity and lack of sleep, but also skipped meals, undereating, and overuse of stimulants, such as caffeine.

To overcome exhaustion the Ayurvedic way, it’s important to sleep regular hours—approximately eight hours a day, preferably going to sleep by 10 or 11 p.m., Klebl said. “Eat regular and healthy meals, including fruits, vegetables, grains, and proteins, without eating too much or too little, and reduce or eliminate caffeine intake.” So, basically, everything you’ve ever heard about eating healthy.

Signs You’re Just Bored or Lazy

Mental exhaustion is a very real thing as well, Gilliland said. “A stressful day at work or working intensely on a project can exhaust our mental fuel for the day, leaving us feeling worn down.” In turn, it can affect our sleep at night since our minds can’t “turn off,” continuing the harmful cycle of poor sleep, he explained.

But let’s be real: Sometimes we just feel unmotivated or lazy. If you’re wondering if that’s the case, take this “test” from Traxler: Ask yourself if you’d feel energized if you were invited to do your favorite thing in the world right now—whether that’s shopping or going out to dinner. “If even your favorite hobbies do not sound appealing, you’re probably physically tired,” Traxler said.

Having trouble with the hypotheticals? Another way to test whether you’re truly exhausted IRL: Create a minimal commitment, and stick to it, Traxler suggested. “Make a minimal (five- to 10-minute) effort to do to whatever you’re trying to do, whether it’s a workout at the gym or cooking a healthy dinner at home.”

If it’s the gym, perhaps your minimum commitment is to simply put on your workout clothes or drive to the gym and check in. If you take that step, but you’re still exhausted and dreading the workout, don’t do it. But chances are, if you’re just feeling mentally—not physically—tired, you’ll be able to rally and follow through with it. Once you’ve broken the inertia (you know: objects at rest stay at rest), you’re probably going to feel a lot more energized.

That, in fact, is the key for any sort of mental fatigue or boredom: Break the inertia.

Same goes when you’re sitting at your desk, feeling your eyelids get heavier and heavier, during a dull Wednesday afternoon. The solution: Get up and move, Traxler said. “Stretch at your desk or in the copy room, or get out and walk around the block for 10 minutes,” she said. “Getting a dose of sunshine is another great way to beat the afternoon slump.”

In Ayurvedic tradition, laziness or boredom is known as a kapha imbalance, Klebl noted, and it arises from inactivity or overeating. The best way to reduce a kapha imbalance is, again, movement. Klebl recommends three to five hours of exercise per week. Plus, make sure not to oversleep, she noted. “Set an alarm in the morning and wake up to practice yoga or go for an early morning walk.” Also, make sure you’re eating lightly in the evening, as well as reducing your sugar intake and your consumption of oily foods and alcohol.

What to Do If You’re Tired, Lazy, or Both

If you’re regularly feeling worn down, take a look at these five usual suspects before heading to a doctor, Gilliland said. “Evaluate how you’re doing in these five areas of your life, and then go to a doctor and run some tests,” he said. “We tend to go in the opposite order, running to our doctor first without evaluating the root causes of our tiredness.” Mentally run through this checklist first:

  • Sleep: Are you getting enough sleep? Experts recommend seven to nine hours.
  • Nutrition: How’s your diet? Are you eating too much processed food, sugar, or caffeine?
  • Exercise: Are you moving enough throughout the day? Most Americans aren’t, which can cause a feeling of lethargy, Gilliland explained.
  • Stress: Stress isn’t always a bad thing, but it can impact your energy levels and sleep. Make time for self-care and stress-reduction techniques.
  • People: Are people in your life bringing you down, or lifting you up? Are you spending enough time with loved ones? Isolation can make us feel tired, even introverts, Gilliland said.

It’s sort of like that airplane oxygen mask metaphor: You have to take care of yourself and your body first before you can help anyone else. Similarly, when it comes to self-care, think of your mind as your phone, Gilliland suggested. “You charge your phone every night. Ask yourself: Are you re-charging yourself?” Just like you want your phone to be at 100 percent battery power when you wake up, you want your body and mind to be the same, he said. Take the time to recharge and replenish yourself each night, and you too will be functioning at 100 percent.