Stretching: The Truth

I’ve always been a stretcher.

Although the tail is new.

But I’ve never liked it.  I think it’s boring, and it makes antsy.  So sometimes I skip stretching and head straight into my run (a run being my workout of choice), but I do it feeling guilty.  I worry that my haste is going to cost me a pulled muscle.

My stretching habit dates way back, all the way to the extended public humiliation that was middle school gym class.  Every class I’d join the gaggle of gangly 12-year-olds doing lunges and toe touches under the watchful eye of Mr. H., my gym teacher and the meanest old man alive.  He barked that stretching was necessary to a healthy physical education, and we believed him.

Later, in high school, I joined the field hockey team, and my stretching became more rigorous and nuanced.  Varsity players lead the warmups.  They were girls of 17 or 18 who seemed sophisticated and worldly to a freshman like me, and I desperately wanted to be like them.  As we stretched, they would call out the names of each muscle group we were working.  “Quad stretch!  Hamstring stretch!” they’d yell, and we’d shift as a unit in the wet autumn grass.  It was important to stretch your quads and your hamstrings and all the rest of it, this much we knew.  If you didn’t stretch, you risked injury, and an injury would send you to the bench.  Then you would never make the varsity team.

Pic of me playing field hockey.

So, stretching is how I was raised.  It’s as ingrained to me as Look both ways before you cross or Never talk to strangers or Don’t pick your nose.  Which is why I was shocked to find out about the controversy.

What controversy?

The thing is that stretching as I know it is a bit of a racket.  Common sense dictates that we stretch to prevent injury and soreness, but actually there is no scientific evidence that it protects against either one.  In fact, there is some evidence to suggest that stretching before running can have detrimental effects—at least when it’s done the way I remember on the field hockey field.

The type of stretching I grew up doing is known as static stretching, which is the process of elongating a muscle and holding it in place.  This type of stretching is intended to increase the muscle’s range of motion, but for an activity like running, a wide range of motion is not actually necessary.  In fact, static stretching can be dangerous if it’s taken too far.  Stretching tears muscle tissue at a microscopic level, and when the muscle heals it becomes a tiny bit longer and more pliant.  A muscle’s natural resistance helps it protect itself, and when that resistance is compromised, it may be slower to stabilize after an unexpected movement, such as tripping over a rock.  This delay can lead to injury.

Studies suggest that static stretching before running can impede progress in other ways as well. This New York Times blog cites an analysis of over 100 experiments assessing static stretching’s effectiveness as a warmup.  The findings would baffle my old gym teacher, Mr. H.  Static stretching actually reduces muscle strength by over 5%, and the longer you hold a stretch, the weaker the muscle becomes.  In short, static stretching before exercise is not a good idea.

Who wants to tell her?

There is another type of stretch that experts recommend for warming up, and it’s called dynamic stretching.  Dynamic stretching is the act of putting a muscle through a repeated, controlled motion, moving it a bit further with every repetition.  This type of stretching gets your heart rate up and your blood rate flowing in preparation for a workout.  It also improves your muscles’ range of motion without straining them the way static stretches do.  Additionally, endless pre-workout stretching sessions are out like your dad’s old leisure suit.  Ten to 15 minutes is enough time to get dynamically warmed up before a run.  You can find a great list of pre-run dynamic stretches here.

If you need a wider range of motion than this, you are maybe not doing "running" the right way. (Photo: (c) Dreamstime.com/Kenneth Ro.)

You don’t have to disregard static stretching altogether.  Many experts recommend bringing it back at the end of a workout, doing toe touches and knee bends like you’re 12 years old in a mid-nineties gym class. But that’s actually a point of contention, and it assumes that you didn’t just kill it so hard on the elliptical that you’re ready to collapse.  If you’re the type of person who hates to stretch after a good run or a solid workout (is there any other type of person?), you can certainly find plenty of information back up your decision.  But a lot of people do like to end with static stretches, because it feels good to do them.  

And feeling good is really the whole point.

A smile is a stretch of its own.

Sleep Debt and a Payment Plan

Full disclosure: the purpose of this post is petty one-upmanship.

Recently I met a man for margaritas.  He was someone I’d been dating, and we had scheduled the meeting so that we could break up.  We both knew the breakup was inevitable, and as such it seemed reasonable to involve cocktails in the transaction.  A spoonful of sugar helps the medicine go down, et cetera.

I’ve prepared a list of your shortcomings that I’d like to read aloud.

Given that I knew what was coming, I really wasn’t looking to draw out the process.  Nevertheless, I slept until almost noon that day and woke up groggy and rumpled, squinting in the midday sun.  I relayed this anecdote to Mister-Right-Now and mentioned that I’d worked several late nights that week and then attended the fabulous (if misleadingly titled) show Sleep No More on Friday night.  I was exhausted, and my body was making up for lost time by repaying my “sleep debt” on Saturday morning.  He patiently mansplained to me that “that isn’t how it works,” so after we parted ways, I went home and looked it up.

In short: yes it is, jackass.

And saying it louder doesn’t make you right.

However, the details are more complicated.

“Sleep debt” is difference between the amount of sleep you should be getting and the amount you actually get.  The average adult requires between seven and nine hours per night, but it’s an individualized need, governed by two internal processes.  One is called sleep/wake homeostasis, your optimal internal balance of time spent sleeping versus time spent awake.  The other is known as your circadian rhythm, a 24-hour cycle of your internal clock.  It’s this clock that helps regulate your daily habits.  If you’ve ever had a full night’s sleep and then found yourself crashing after lunch, you can thank your circadian rhythm.  Circadian rhythm can be affected by elements such as sunlight or temperature.  It’s also the reason you experience jet lag when you fly across time zones.

Cicadian rhythm, though, is something totally different. Via here.

You don’t need a science degree or a wellness blog to tell you that losing sleep has mental and physical consequences.  It can make you drowsy the next day (duh) as well as inattentive and irritable.  Sleep debt increases levels of the stress hormone cortisol and lowers your body’s ability to repair muscle, process glucose, or maintain your immune system.  It’s also been linked to inflammation (which can have extensive consequences to your health, including heart disease).

The problem is, missing out on sleep during the workweek is hella common.  People have packed schedules and busy lives; this is what the 21st century is about.  But the more sleep debt you accumulate, the less likely you are to recognize it as debt.  Grogginess and caffeine dependency can become normalized as elements of your daily routine, masking a larger issue.  Eventually, you could find yourself at risk for the more serious, long-term effects of sleep debt, like diabetes, stroke, obesity, and the aforementioned heart disease.

Although it’s totally possible that you have good reason to be awake. Via here.

So what happens when you try to pay up?  One study found that repaying a six-night sleep debt over the course of three days helped to level out daytime sleepiness and inflammation, but participants’ attention levels did not return to baseline at the end of the study.  This is bad news for fans of all-nighters, because when attention levels are off, performance and productivity can falter.  In a different experiment, researchers found that participants who slept one long night were able to offset the effects of a sleepless week—but only for about six hours.  After that, performance worsened the longer the person was awake, and their risk of making errors increased.  Ultimately, while sleeping in for a weekend can help undo the effects of a week of late nights [jackass], it’s not going to be enough if you have a chronic issue.

Incidentally, modern-day habits are not reflective of the sleep habits of our forbearers--and that might be part of the problem.  Since the invention of the lightbulb, the average person sleeps a whopping 500 hours less per year.  In addition, the modern concept of a single, uninterrupted night of sleep was not always the priority.  In a recent New York Times piece, anthropologist T.M. Luhrmann cites the work of historian Roger Ekirch, explaining that in days of yore, people fell asleep for their “first sleep” shortly after nightfall.  “Then they awoke, somnolent but not asleep, often around midnight, when for a few hours they talked, read, prayed, had sex, brewed beer or burgled.  Then they went back to sleep for a shorter period.”  This passage speaks to the way that modern civilization has affected human departure from our own circadian rhythms.  It also shows that our forefathers had rather bizarre means of keeping themselves entertained.

“Let’s see, the beer is brewed, the prayers are said, the wife is satisfied... I guess it’s time to rob somebody.”

Ultimately, while sleep debt can be repaid, it won’t happen overnight.  Just like your student loans, it’s a debt you’re likely to carry with you for quite some time.  Chronic sleep debt is paid off in installments, and the only way to do it is to listen to your body and let your own internal clock take charge.   Go to bed when you’re sleepy and get up when you’re ready, and little by little your body will show you exactly how much sleep you need.  You’ll be sharper, less stressed, and faster to metabolize.  Your body and brain will thank you.

And you’ll wake up ready for anything.  Jackass. Via here.