Why do songs sound slower when exercising?

September 12, 2005 8:09 AM

When I'm running and listening to music through headphones, songs sound slower than normal. Why is this?

I use an mp3 player when running (iPod mini, if it matters) but also listen to the same songs in the car, at work, etc. I've noticed that songs sound much slower, tempo-wise, when I'm running, especially when I'm really tired and my heart rate is high. For example, up-tempo songs with a fast beat just don't sound as "peppy". Is there a physiological reason for this, or is my mp3 player running slowly, or is it just mental perception?

posted by chos to sports, hobbies, & recreation (12 comments total)

I don't think there's any accurate or reliable explanation for purely subjective experiences. But to hypothesize, maybe the brain waves are running quicker during strong exertion, thus the brain processes at a faster rate and time "outside" seems to slow.
posted by rolypolyman at 8:55 AM on September 12, 2005

I have experienced that same feeling. Have you also been in a situation were a second felt like more than 10? It could very well have something to do with how you respond to resting heart rate, and the endorphins going through your body.

Either way, it is definately not your Mp3 player that's doing it.
posted by Dean Keaton at 8:58 AM on September 12, 2005

It's nothing to do with speed and everything to do with pitch. Sounds heard through headphones tend to sound like they are pitched slightly lower. This is to do with air pressure and the fact that, proportionately, sound coming through headphones travels through more bone than sound coming from speakers. It makes mixing on headphones very difficult (and thusly I tend not to recommend doing so to anyone - get a good set of monitors, dagnamit!) as taking the 'phones off and listening to the same mix on headphones will have it sound brighter, higher and yes, faster. (The faster is just an illusion - of course, the music doesn't change speed, but lower sounds trick our brains into thinking they're slower sounds...)
posted by benzo8 at 9:20 AM on September 12, 2005

I've experienced this, centered around being physically and mentally tired from a long commute. No idea whether it's physical or mental or a combination of the two, but it definately seems to be a sensory problem, not a technological problem.
posted by Jeff Howard at 9:28 AM on September 12, 2005

interesting... i have noticed the same thing while on the treadmill, and thought about it a little bit.

in a (synchronous) computer system, the "perception" of time is controlled by one or more oscillators running at a set frequency. these oscillators need a certain amount of voltage to oscillate at a stable frequency. if you reduce the voltage, some oscillators oscillate more slowly, and some fail to start oscillating at all. ferinstance we have several musical toys with low batteries, and as the batteries wear out the songs play slower and slower and slower... the computer has no "idea" its playing more slowly, its just doing what its doing same as always, yet the pitch and tempo of the songs are slowed down.

i suspect something similar might be going on with us, if you believe that we are biological computers of sorts. the timebase for our brain must be controlled by chemical reactions in our neurons, and as our metabolic rates change probably the rates of those reactions change, leading to a change in perception of the flow of time.

also, at least in semiconductors, the flow of electrons is influenced heavily by the temperature of the semiconductor. i dont know if the same is true for neural tissues/neurotransmitters. dammit jim, i'm an engineer, not a doctor!
posted by joeblough at 10:18 AM on September 12, 2005

And I thought chos was probably running at close to the speed of light.
posted by Tuwa at 10:32 AM on September 12, 2005

Thank you for asking this, this has happened to me as well. I don't think it's the headphones, as benzo8 describes, as I don't experience it when I use headphones at work.

FWIW when I have to listen to the same songs twice on the same run, they sound much slower the at the end of the run than they did at the beginning.
posted by samh23 at 10:37 AM on September 12, 2005

Maybe it's like a smaller version of that Doppler effect thing where ambulances drop in pitch after they pass you by.
posted by First Post at 10:39 AM on September 12, 2005

I've wondered if adrenaline has any effect upon time perception. I almost got in a hairy multi-car accident yesterday, and it seemed like I had plenty of subjective time to look around, apply brakes, decide when to try and bail into another lane amidst high-speed rush-hour traffic. The passenger saw everything as happening instantaneously, and it probably almost did. I also notice that when onstage, if I forget a line or something, it seems like I have plenty of time to root around in my brain and dig up the correct one (or make something up). In rehearsal, invariably I just go blank and stand there stupidly because it seems like I have no time to think. Weird.
posted by umberto at 11:07 AM on September 12, 2005

I'm pretty sure that it is because your brain waves are in high beta (probably over 25 Hz) when you are exercising. Our bodies don't have much of a short-term clock other than brain rythm and heart rate. The longer-term clock (in terms of hours) is driven more by hormone levels.

The rhythm of your movements (including your heart) drives your brain into developing a rhythm which is a lower harmonic of your movements. For example, if you are jogging at 120 steps/sec, your brain probably has a rythm of 30 Hz, the 4th lower harmonic. When listening to music at, for example, 80 BPM, which has a 4/4 meter, you brain hears 2.6 beats per cycle, or 2/3rds of a measure, which seems slow.

At rest, but alert, your brain is probably operating around 15 to 20 Hz, meaning your brain would hear 4 to 5.3 Beats and 1 to 1.3 measures per cycle of 80 BPM, 4/4 music, which would make it want to work faster.

In short, we like to hear a complete measure per brain cycle. Without other influences, our brain will try to match the rythm of the music being heard. When exercising, this is impossible, since moving has much more influence on our brain than hearing something.

One exercise that (obviously) helps your brain get in sync with the music is dancing. When dancing to music, your brain is almost always in complete sync with the beat of the music, and your movements. Your brain likes this, and rewards you with a feeling of pleasure.

You can try changing your brainwaves more directly with software that generates binaural beats. I've used SBaGen.

Of couse, all this is somewhat pseudoscience and new-age bullshit. And I don't know what the hell I'm talking about.
posted by darkness at 11:35 AM on September 12, 2005

Tuwa, can't say that I was running at speeds approaching the speed of light. But it would be cool if that was actually the reason.

Glad to see I'm not the only one who has ever experienced this - thanks for the comments.
posted by chos at 11:41 AM on September 12, 2005

My WAG is that, much like a strobe light gives the impression that you vision has slowed, running causes your inner ear to "strobe" in effect. Perhaps the bouncing done when running causes your hearing to waver (due to a mechanical process in the ear or eardrum) enough to cause this strobe effect - but not so much as to be apparent to the dips. So, you are hearing clips, in a sense. This gives the illusion that the sounds have slowed. Probably especially noticeable against a song which has a noted speed and cadence. You'd probably not notice it against everyday random sounds or someone talking.

Again, just a guess.
posted by qwip at 7:57 PM on September 12, 2005