How Much?/ How Fast?

blurred bikerHappy Sunday! Did you enjoy the lovely summer solstice? The longest day of the year, solar-ly speaking! The official start of summer!

And in marking the start of this outdoors-y sunshine-y season, I figured it’d be fun to bring up some of the national guidelines for physical activity! Yes… fun! It’s like reviewing the rules before we let the “summer games” begin!

Here’s the thing about guidelines. They are just that- a guide, an outline of how to proceed. An outline is something that comes before a first draft. If we were writing a paper, the guidelines would be like the writing prompts (apologies- summer session means I still have school-brain).

With physical activity it’s the same concept. It’s a place to start. Something really basic that can be molded into your routine- to be part of your life. Like writing a paper or a book, making a fitness routine can require several drafts. And as you find yourself in different stages in your life, you may need to revise, and reorganize, and update to the next “edition,” so to speak. (I seem to be revising my fitness plan each semester!).

But the guidelines are great place to start- or re-start, as the case may be.

So what are they?

In 2008, the US Department of Health & Human Services (HHS), a government organization, released the first national Physical Activity Guidelines for Americans (PAGs). Based in research, they give recommendations for everyone, age 6 and up (chances are, if you’re reading this, you are covered under this umbrella).

The PAGs are very similar to the evidence-backed guidelines of the American College of Sports Medicine (ACSM is the organization that certifies exercise physiologists and personal trainers). The ACSM released their latest guideline position statement in 2011.

Due to the way exercise research has progressed, we have a huge amount of evidence regarding cardio fitness. And due to a lack of studies, we have much less science to go on when it comes to resistance training. However, this is beginning to change, and the great importance of resistance training is being revealed! I will bring it back up in a future post. But for today, let’s stick with the cardio.

Both organizations mentioned feature a main guideline regarding adult cardiorespiratory fitness, stating that:

All adults* should participate in at least 150 minutes of moderate-intensity activity per week.

This is less than 3 hours per week. Less than 30 minutes per day.

This does NOT mean- “Hey, I’ve never exercised before. I guess I should go out for a 3 hour bike ride!” I mean, it can potentially mean that, but this might be risky depending on who you are!

The terminology “moderate intensity” is vague for a reason. Moderate, in a general way, means something different for everyone. It’s based on YOUR current fitness level. The “moderate” pace of an Olympic swimmer doing laps is most likely going to be far more intense than the pace that feels “moderate” to the average Joe who dives in for a recreational dip. More on this in a minute.

At this point, there is no definitive recommendation regarding whether it is better to do the exercise all in one go versus spread out over the week. Though they do recommend that exercise bouts be at least 10 minutes long. (Like I said, it’s moldable to your routine).

Some extra motivation: More and more studies are beginning to show the impact of sedentary activities (sitting, lounging, etc.) on our health. And what’s even scarier is the new theory that this type of behavior, in excess, may actually NEGATE the other active behavior in which we engage.

What does this mean? Sit less. Have fewer health consequences. At least that’s what the evidence is showing in a corollary fashion. (Something is better than nothing. Need some quick ideas? Start here).

Confession: I didn’t know the guidelines existed until I started grad school, and took my first exercise physiology class. Pathetic? A little. I guess I was lost in the yoga cloud, not paying attention to the rest of the exercise world. This has since changed. But I’m not the only one that didn’t know! A recent NY Times article revealed part of the wide knowledge gap in which the guidelines seem to be hiding.

The majority of subjects involved in the study addressed in the article were more or less in the dark as far as the guidelines were concerned. And when given the guidelines, most were unable to identify a moderate pace when they were asked to exercise. In other words, most of them overestimated how hard they were working.

Now, I mentioned that “moderate intensity” is a pretty variable term. Moderate for you is likely different than moderate for me. So what are we supposed to do?

Heart rate is one of the hallmark tools used in cardiovascular exercise measurements. It requires either a heart rate monitor, or ability to accurately take your own pulse. But this can be a great way to familiarize yourself with what different intensities of activity feel like to YOU.

An easy trick to figure out the numbers involved:

Your max heart rate is roughly your age subtracted from 220. For example, if you are 32, your max heart rate is approximately 220 – 32, which equals 188 beats per minute.

The meaning of “moderate intensity” as defined by the ACSM and HHS is not super clearly explained in the general position statements (the formal statements are a bit more detailed). The Times article suggests using the Canadian guidelines which define “moderate” as between 64% and 76% of your max heart rate. The ACSM Guidelines manual similarly gives a range between 64% and 77%.

129 volunteer subjects- aged between 18 and 64 years- were involved in the study mentioned above. Of the 129, when asked to demonstrate moderate-intensity exercise, only a quarter of them got their heart rate up past 64% of their max- i.e. to a level considered beneficial.

Food for thought…

Summer lends itself to getting outside to move. It’s warmer, it’s easier, and there are so many more fun, accessible options available. It’s officially summer! So get going! Start your next “draft” while it’s light out both earlier and later! Figure out what works while nature is making it easier to do so!


*If you do not regularly exercise already, it is recommended that you consult with your doctor before starting a routine, particularly if you have a cardiovascular or other chronic condition. Be safe!


One thought on “How Much?/ How Fast?

  1. Pingback: Them Bones, Them Bones… | Healthy Prongs

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s