Thursday, January 14, 2016

A strength workout has long-lasting effects

Dorshka doing a set of 5 heavy deadlifts
Do you feel so good after a strength workout? It's a different feeling than the "runner's high" you get after a long endurance workout. Living in Boulder, I'm sure you've been talked to ad naseum about the runner's high and know all about it, even if you don't get it yourself. But what's up with the good feeling you get from a strength workout?

Well it turns out that your muscles aren't just there to lift things, they're also part of your endocrine system. Muscles are active in signaling your body to do things - they send out molecules called myokines. When you do a heavy workout, your muscles use myokines to signal to your body that they're being stressed and that they need to be stronger. But they do a whole lot more than just that! Some of myokines released hit your brain and make you feel better. A heavy squat in the evening makes the stress of a work day just melt away for me.

Sometimes it even goes beyond making you feel better; it actually does make you better. When worked, your muscles also use myokines to signal to your immune system to get stronger. That's why when someone comes into the gym with a cold or sore throat, I never let them do the normal workout. I just say do a set or two of heavy squats, then go home and sleep. Those heavy squats kick-start your immune system, and I've noticed that people get better pretty quickly. (I also do some heavy squats when one of you comes in sick, and it's kept me from catching what you have too!)

Even beyond that, the linked article talks about one of the myokines that has anti-obesogenic, insulin-sensitizing, and anti-inflamatory effects, even long after the workout is done. I know of at least two biologists at the gym who can read the article and tell me even more about this, so I won't go into too much here since I'm not the expert. My interpretation of this is that there is a compounding effect of a strength workout beyond just the work done.

Here's how I see it:

1 - You can burn a few calories in a strength workout. It's not very many calories (talk to the rowing club about how hard the 300 Calorie Revenge of Pie workout was), and I don't subscribe to the calories-in-calories-out model, but that's a rant for another day.

2 - You can raise your metabolism for a day or two after the workout. All the fitness articles talk about EPOC, or Excess post-exercise oxygen consumption, which is extra energy you're burning after you're done working out. This is the first layer of compounding: you get more out of the workout than just the workout.  And it's much better for a strength workout than a "cardio" workout.

3 - A third layer of compounding is that these myokines are signaling to your body to adapt in a way that helps you process your nutrients better. So in #1 you have your first-order effect of burning your calories based on how much work you're doing, and then in #2 you get some bonus because your metabolism has ramped up. But in #3 you're actually processing nutrients better and getting more out of the workout than you put in. The strength workout makes you more insulin sensitive (a good thing).

I'm going to suspend my criticism of the calories-in-calories-out model to help make a simple physical picture: imagine a bucket of water. Water goes into the bucket and makes it heavier - eating, calories in.  You can scoop water out of the bucket making it lighter - exercise, calories out.


A strength workout starts by scooping water out of the bucket. Effect #1 above is that the bucket gets lighter the more water you scoop out, but it still keeps getting filled up by the hose.

Effect #2 is akin to extra water splashing or sloshing out along with your scooping. A harder workout would shake the bucket harder and more water would just slosh out. The EPOC can be viewed as the water sloshing out of the bucket after you're done scooping.

Effect #3 (due to signaling from the myokines) is like pointing the hose away from the bucket. Rather than working hard trying to keep up with the hose, we work smart and stop the hose from filling the bucket.

Rather than just viewing a strength workout as the raw number of calories burned during the workout, think about the downstream effect the workout has too. I hope you see now that the effects of strength training are more complicated and interesting than they might seem on the surface.
Workout
strength - add weight from last time (more info) 

squat 3x5 

then


8 rounds for time:
as a complex (same bar, same weight, don’t put the bar down)
3 hang snatches
3 overhead squats
3 squats
3 btn press