Thursday, January 18, 2007

Is the Select Comfort air mattress good for sex? A PoS experiment

If you're eagerly anticipating part 2 of Sex and Sensibility, we'll have that for you next week.

In the meantime, we decided to send two of our writers, Buzz Skyline and Martica, into the field to do an experiment inspired by a portion of the Physics of Sex post Sexual Rhythms.

Specifically, we wanted them to see what physics could tell us about the Select Comfort brand adjustable bed. We hoped they would learn enough to help you determine if it's the best bed for your love life.

You can listen to roboreader Heather interviewing Martica and Buzz in our latest podcast, or read the transcript below, to find out what (if anything) the Sleep Number bed has to offer for sex.

Skip to the tip in this week's post, if you're in a rush.


In any case, please take part in The Great Physics of Sex Bed Test. We want you to test out your bed and send us the data so that we can figure out, once and for all, what type of bed is best for sex. But don't do it for us. Do it for yourself. Do for the world. Do it for science.



TRANSCRIPT OF THE SELECT COMFORT BED TEST INTERVIEW

Heather: Welcome to the Physics of Sex podcast. My name is Heather.

If you've been listening to our past episodes, you know we usually give a little lecture about a fascinating aspect of physics, as it applies to your love life. But this week, we decided to try something different.

We sent two of our writers into the field to do a few experiments on an unusual kind of bed, in order to find out how it might affect your sex life. Here to report on what they found out about the Select Comfort sleep number bed, are Martica. . .

Martica: Hi Heather.

Heather: . . . and Buzz Skyline.

Buzz: Hi Heather.

Heather: So guys, you ventured out to test a bed. Did you do what I think you must have done? How'd you keep from being arrested?

Martica: Well, we didn’t actually do anything that's not appropriate in a mattress store. We actually just went and jumped on the bed.

Buzz: Well, we sat and bounced on the bed.

Martica: Exactly.

Buzz: We didn’t stand on the bed.

Heather: OK, well tell us about the bed.

Martica: It’s a Select Comfort Sleep Number bed, which [allows you to] change the firmness of the mattress.

Buzz: You can change the amount of air inside the mattress.

Martica: Right.

Buzz: And they call it the firmness.

Martica: It’s a big air mattress with a pump and a little remote control which you can use to pump the air in or let the air out and that changes the firmness, what they call the firmness, of the mattress.

Buzz: And it basically is just inflating this bladder that’s inside the bed instead of springs.

Heather: So this is the bed Lindsay Wagner promotes on TV. Great. How did you do the experiment?

Martica: We sat on the bed and bounced up and down.

Buzz: At different numbers. We set it for different numbers and we took turns bouncing on it. Martica bounced on it a few times at different settings and I bounced on it at a few different settings, a few different sleep number settings, and the last time . . .

Martica: We sat next to each other and bounced up and down at the same time, which is actually really hard – but fun. (laughs)

Heather: What sort of results did you expect?

Buzz: So, what we thought would happen was we assumed the sleep number really was what you call firmness, which on a spring would basically be the spring constant. It would tell how strong the springs are. And that means that as you turned it up it should increase your resonance frequency- the frequency that you bounce on the bed. And as you turn it down, it should decrease your resonance frequency. And so we started out with Martica on the bed, and what we found was no matter what sleep number we chose, she bounced at about the same rate.

Martica: I was trying! (laughs)

Buzz: It wasn’t her fault. It was obviously the physics. And so we thought there must be something wrong. So I sat on the bed and tried it for several numbers and I also bounced at almost exactly the same rate every time.

Martica: But a little bit more because you’re a little bit heavier than I am.

Buzz: Yeah, I bounced slower than Martica did because I weigh about 50 pounds more. So you would expect it to be a little slower, and it was a little slower, but by the same amount every time than Martica’s bounce was.

Martica: No matter whether the bed was really, really, really firm and full of air or really, really, really soft and the balloon was almost flat.

Buzz: So basically that means that whatever the sleep number tells you, it doesn’t really tell you the firmness in the same way that a bed is firm, it doesn’t tell you how firm the springs are. It’s changing something else.

Heather: All right then, what's going on?

Martica: So what it actually is that’s changing is the damping of the bed. It’s like having a giant pillow that you can compress and make it firmer or make it softer.

Buzz: Yeah. So if you were to open the bed and look at the bag, you would either see that it was completely full at a hundred percent, or a hundred sleep number, but usually it was kind of floppy.

Heather: So the sleep number doesn't matter for sex? You just set it wherever you want and things don't change?

Buzz: Well we did find that there was a change as we turned the sleep number up or down.

Martica: Right, it got harder to bounce on.

Buzz: It was more . . .

Martica: It took more energy because you’re bouncing on a less inflated balloon, basically.

Buzz: You are tuning something. You’re not tuning the spring constant, but we were tuning the damping. It made it harder to maintain a bounce because it was . . . it wasn’t changing the spring constant, but it was sucking energy out of the bed, it was damping the energy. It meant that we had to work harder to bounce when you turned the sleep number down, which corresponds to turning up the damping but not changing the spring constant.

Heather: Do people who actually buy the bed think about this sort of thing?

Buzz: In fact, we had the same question. So I went back when the store was closing and there weren’t any customers to distract the salesman, and I asked him that very question. And this is what he said.

(Mall noise)

Buzz: And so the feature we’re doing is a question of whether or not some beds are better for a love life than other beds.

Salesman: Uh huh.

Buzz: And we’ve gone around and we’ve measured basically the resonance frequency of various beds and . . .

Salesman: Uh huh.

Buzz: . . . things like that to try to understand how they’re different.

Salesman: Huh.

Buzz: So I was wondering – do people ever take that into consideration? When they talk to you when they are about to buy a bed, is that something that ever comes up?

Salesman: Nah, it never comes up. Maybe, maybe they think about it, or maybe they talk to each other about it.

Buzz: So it’s not like a waterbed store where you know what they’re there for . . .

Salesman: Right.

Buzz: This is more for . . .

Salesman: I’ve never, never heard anybody say anything like that.

Buzz: How long have you been sellin’ the beds?

Salesman: Since November.

Buzz: Oh OK, so you haven’t been doing it too long. So some people may think that . . . But if they did there’s not . . .

Salesman: I’ve slept on one. I’ve slept on one for about six years. But my wife and I, we don’t talk about it.

Buzz: You don’t adjust the pressure . . .

Salesman: No.

Buzz: . . . or anything?

Salesman: No no. Nope.

Buzz: Oh OK. (laughs) Alright. Well I know they’re strange questions.

Salesman: No no no. It’s all part of research.

Buzz: Exactly.

Salesman: I’m doing my part for science.

Buzz: OK. Alright.

(Mall sounds fade.)

Heather: So, having put the Sleep Number bed through it's paces, what are your recommendations?

Martica: Well if you already have a sleep number bed then you can turn it up for sex, if you want to make sure you’re getting the most bounce for the energy you put in.

Buzz: With a regular mattress, you can add damping. You can add something like comforters or pillows or something. You have to add additional material to make it softer to make it more comfortable or to change the rhythms of sex. Whereas with the Sleep Number bed you could potentially, with just this one adjustment, quickly go from what’s comfortable for sleeping to what’s comfortable for sex and back again.



Heather: Do you have plans for follow up experiments?

Martica: We plan to go to a mattress discounter store where there will likely be more mattresses with springs inside of them rather than air inside of them, and jump up and down on the beds there as much as they’ll let us. And ask some of the same questions. If maybe people who buy spring beds are looking to see how their sex lives will be changed by these beds. And if we go to a waterbed store, maybe people are even more interested in sex when they come into a waterbed store looking to buy a waterbed.

Buzz: It would be a completely different experience. And we could also consider alternative sleeping surfaces, like futons.

Heather: That's great. You've certainly given us something to think about. Thanks for stopping by.

Martica: Thanks Heather. It was great to talk to you.

Buzz: Bye.

Heather: After the select comfort adventure that Martica and Buzz went on, it occurred to us to ask our listeners and readers, to tell us about your beds. What type of bed do you sleep on? Is yours good for sex? Is it fast or slow? Do you prefer lots of damping or just a little?

We'll post instructions on our website, ThePhysicsOfSex.org, to let you know how to send us some data. We'll analyze it and hopefully report back with the results in a few weeks.

Thanks for listening to the Physics of Sex podcast. I'm Heather.

Download us next time for the second segment of last week's show, part two of Sex and Sensibility, the physics of the nervous system.

Bye for now.

END OF TRANSCRIPT





The Great Physics of Sex Bed Test


It's this easy.

Send us an email or write in the comments section the information you collect by following these instructions.

1. Tell us what kind of bed you have (spring mattress, waterbed, space-age foam, futon, air mattress, etc.)

2. Estimate the damping on your bed - is it plush (like a pillow top bed), moderately padded, or a plain mattress?

3. Measure your bed's resonance frequency by

a. getting a watch with a second hand

b. sitting on the bed and bouncing at the rate that feels most natural

c. timing how long it takes to bounce 25 times

d. It couldn't hurt to do the experiment a few times, or even get your partner or friends to try it. Be sure to note both the time it takes to bounce 25 times and the weight of the person bouncing. We'll need both numbers to calculate your bed's spring constant.

4. Tell us whether your bed is good for sex on a scale of 1 to 5, where five is Nirvana and one is like doing your taxes.

5. Send the information to us in an email to BuzzSkyline@gmail.com, or paste it into the comments section for this blog entry.

13 comments:

Anonymous said...

. I have a very old sealy king sized bed

2.15 times

d.134 lbs

3. 4 (but maybe cause I just love sex?!) its pretty firm, but the springs are kind of old

4.plain mattress

Buzz Skyline said...

Hmm. Do you mean 15 times in 25 seconds? or 15 seconds for 25 bounces?

(For anyone else doing the experiment, I was hoping for you to tell me how long it takes to bounce 25 times. Either way gives an answer, but it's simpler and easier to analyze if we all do it the same way.)

If it's the first, the spring constant (k) of your bed is

k={(2 pi)^2(15 bounces/25 seconds)^2}* 61 kg

{the symbol ^2 indicates squaring the quantity in the parentheses}

k=856 Newtons/meter

If you mean 25 bounces in 15 seconds

k={(2 pi)^2(25 bounces/15 seconds)^2}* 61 kg

or k= 6661 Newtons/meter

The first number sounds very low to me. The higher value is close to what we got for the Sleep Number mattress. Drop me a note to confirm which you mean.

I'll add it to the data as soon as we get it figured out.

Thanks for helping.

All the best,

Buzz

Anonymous said...

-Spring mattress

-25 bounces in 14 seconds

-190 lbs

-it's too soft for my taste, so I would give it 2 stars for sex (although it's nice to sleep on)

-thick pillow top for lots of damping

Buzz Skyline said...

Thanks anonymous!

I'd love to hear from anyone,regardless of the bed they use. But in particular, I'd like to find out what people think of the memory foam beds (Tempurpedic is the most famous, but I've seen other brands and memory foam pillow tops).

Personally, I think the foam mattresses are GREAT for a good night's sleep, but AWFUL for sex. Is it just me?

I don't have Bed Test data for one because I've only experienced memory foam in hotels, and hadn't thought of the experiment at the time.

-Buzz

Anonymous said...

I'm in Iraq and I sleep on a US Army issue canvas cot. It does not have any bounce at all (unless something close by has exploded in which case even the ground bounces). I have not tried having sex on it, unless partnerless sex counts in this survey, in which case I would say it is suficient for the task. I'm sorry to say when I finally do get home I doubt my wife and I will go 25 "Bounces" without something happening (at least for the first few months) so I won't be of much help with your research then either, but from the way I am feeling now I would bet I could rattle off 25 "Bounces" in 5 seconds flat, on ANY surface, no matter how firm or soft.

Anonymous said...

I don't have to do all of this to tell you my 3 1/2 year old pillow top mattress is NOT good for sex. It has a tendency to sink beneath the weight of 2 average-sized partners and it's hard to get a foot-hold as it were.

*His* old futon, on the other hand, is awesome. Firm with good hand/foot gripping. Would much rather spend the night at his place if we want sex. My place if we want sleep.

Anonymous said...

1. Wal-Mart foam mattress, b4 that a futon

2. total damping

3. no bouncing/no springs

4. both are 4-5 b/c of good gripping, no random motion (once you hit the spot there is no bounce to take it away), futons and memory foam are GREAT for sex, total support and traction for all positions.

Anonymous said...

this is so interesting..

Anonymous said...

i agree, thrilling...

Anonymous said...

I've found that a is the best for sexually activity ;)

Unknown said...

I'm not going to bounce on my bed with a stopwatch, but I will tell you that buying a new mattress has killed our sex life. We just moved across country and could only take one mattress with us. My girlfriend had a relatively new pillowtop mattress with lots of bounce. I had a brand new TempurPedic mattress. For sleeping, the TempuPedic wins every time. For sex, it's a real disappointment. If your love life only fits within the description lines of "making love", really any mattress is suitable for slow, rythmic movements. On-the-other-hand, we like to get crazy, almost to the point of laughter sometimes. I want to be helpfully descriptive without sounding perverted; the old mattress had a sort of bounce to it where once we got movin' it would sort of keep us going w/o any effort at all. Hope that makes sense. That stupid commercial where they have the wine glass and the girl jumping on the bed proves my point exactly. I can jump on my TempurPedic all I want and not spill my beer. Except I can't jump very high, so I'll need lots of beer to drown my resentments about choosing the wrong mattress.

Unknown said...

I'm not going to bounce on my bed with a stopwatch, but I will tell you that buying a new mattress has killed our sex life. We just moved across country and could only take one mattress with us. My girlfriend had a relatively new pillowtop mattress with lots of bounce. I had a brand new TempurPedic mattress. For sleeping, the TempuPedic wins every time. For sex, it's a real disappointment. If your love life only fits within the description lines of "making love", really any mattress is suitable for slow, rythmic movements. On-the-other-hand, we like to get crazy, almost to the point of laughter sometimes. I want to be helpfully descriptive without sounding perverted; the old mattress had a sort of bounce to it where once we got movin' it would sort of keep us going w/o any effort at all. Hope that makes sense. That stupid commercial where they have the wine glass and the girl jumping on the bed proves my point exactly. I can jump on my TempurPedic all I want and not spill my beer. Except I can't jump very high, so I'll need lots of beer to drown my resentments about choosing the wrong mattress.

Anonymous said...

Spring constant is only a part of the situation. If it is not supportive enough where her butt is, it will depress at that area, basically folding her at the hips and reducing penetration, possibly causing "fallout" and perhaps even pain. This aspect REALLY needs equal attention.