Your bedroom should feel like a sleep palace.

But if you're collapsing onto a mattress that's been beaten into submission over the years—decades, even—you're doing your body a disservice.

A typical mattress (i.e., a moderately priced "innerspring" model) starts to wear down after about five years. And by age 10, it's basically a skeletal box of springs, according to research published in the journal of Chiropractic Medicine.

As you'd imagine, sleeping on a crappy mattress leads to crappy sleep. You're more likely to suffer sleep-related pain and fatigue, wake feeling drained, and experience shoulder aches, neck twinges, or lower back discomfort. And if you're thinking about just pushing yourself through a rough night like you do with your tough workout routines, consider this: If you live to 75, you'll spend 25 of those years asleep.

The easiest fix? Getting a new mattress every five to eight years. And if that sounds like a lot of cash to fork over, it's probably because it is: Mattresses can cost hundreds, even thousands of dollars.

The better, smarter solution? Getting a personalized mattress. Here's why you should consider a custom-made bed:

1. It's hard to know what kind of mattress is best for you

Participants in that Chiropractic Medicine study didn't just sleep better on a new mattress because it was brand-spankin' new. It could also have been that they were sleeping on medium-firm mattresses, researchers theorized. So, while some experts suggest that finding the comfiest mattress is paramount, others argue that "comfort" may not necessarily be what your body needs.

For example: Everyone likes the idea of sleeping on a mattress that envelopes you in plushy softness. But if you have chronic low back issues—diagnosed scoliosis, a herniated disk, or nagging deadlifting pain—a feather-soft mattress can actually exacerbate your issues by allowing your spine to cave in. Likewise, the study found rock-hard mattresses didn't alleviate back pain either. (Interesting, since the researchers note how 75% of orthopedic surgeons suggest a firm or super-firm mattress to relieve pain.)

Point is, people generally aren't great at determining the best mattress, even after a superficial "test drive" in the store. In fact, when allowed to test mattresses in a typical showroom, most men and women don't choose a mattress that minimizes overnight tossing and turning, and maximizes optimal sleep, according to another study from the Research Triangle Institute.

So: What's the best objective way to find the right mattress? Bodyweight is a good place to start, argues lead study author Bert Jacobson. And that brings us to Helix, which is currently the only website that offers a sleep quiz to help you personalize how your mattress is made.

Helix's algorithms account for how much you move while sleeping, your sleep position (back, side, stomach), whether you get hot (or just sweat all the time), how much pain you feel in the morning, and how well you currently sleep.

And that brings us to our second reason you should consider a personalized mattress:

2. You're a big dude

Say you're just a large man, like The Rock or John Cena. Broad shoulders can create pressure points, leaving you with tight, achy shoulders. With Helix, you'd indicate those shoulders as "hot spots"—and the website will tell you that you'll likely need a firmer mattress to make sure your body isn't sinking in certain areas.

Likewise, if you're built like a linebacker you're going to need more support and pressure relief.

3. You're a stomach- or side-sleeper

Stomach-sleepers need more support than back-sleepers, since your spine will dip—especially if the mattress sags. Combine that with a big, beefy pillow, and a flimsy mattress will put your spine in a U-bend most of the night. (By the way: "firmness" and "support" are different: Even a hard bed doesn't necessarily support your body where you need it most.)

Side-sleepers, meanwhile, need greater "bounce," so their mattresses can give under one shoulder, arm, and hip.

4. You sweat a lot at night

Sweaty sleepers need a special foam arrangement so the heat doesn't get trapped in the layers.

Memory-foam mattresses might be comfortable, but they collect a ton of heat, and they can actually cause (or even worsen) back pain because they don't brace vulnerable areas of your back.

5. You hate mattress stores

Ever bought a mattress? It's like buying a used car, only worse. You've got a frenzied salesperson staring at you while you lie on half a dozen mattresses that have already been rolled around on by hundreds of other people (woof), putting the pressure on you to buy right now for an unbeatable price.

Then you've got to lug the thing out of the store and into or on top of your car (or pay to have it delivered). It's awkward, miserable, and—here's the kicker—you might not even like the damn thing. Plus, brick and mortar stores charge more for mattresses because they, and the mattress brand, all get a piece of the pie. Personalized mattresses from brands like Helix (or online sellers like Casper) go straight from the factory to your bedroom. With online shopping, you don't feel like you're in a high-stress, life-or-death situation.

So ask yourself: Are you happy with your current mattress? Do you wake feeling totally rested and pain-free? (Answer these four questions to see if you're getting quality sleep.) When did you get your mattress? If your overwhelming feeling is 'meh, it kinda sucks,' and your mattress was a hand-me-down you got from a friend of a friend who swore there were no bedbugs but it's been around for as long as you, you're in the market for a new one.