Sunday, July 28, 2013

Playing the Numbers: Heart Rate

Photo credit: FratmenJonah
I've really just begun to look at heart-rate training. I know I keep my body in my target heart rate, described below, but I've not begun to maximize my cycling efficiency with heart rate zones. That's the next step, and this preliminary outline is just the beginning. Use it to gain a general understanding of the topic. For a general discussion of this topic for cyclists, read here.

As a preface: just get out and bike. Any amount of doctor-approved aerobic exercise is more likely than not to be beneficial. That being said, you can maximize your workout and make it more safe by
knowing something about heart rate and its effects on exercise.

I. Simple: Resting and Target Heart Rates

The American Heart Association recommends these steps:

A. Determine your resting heart rate.

This you do in bed when you first wake up. You can follow the American Heart Association's instructions, or you can strap on your Garmin and use it to determine your heart rate at rest.

Resting heart rate is unique to each person, so you can't just go by a chart. The average is 60 to 80 beats per minute. Athletes typically have lower resting heart rates, which can be as low as 40. If you're just starting an exercise routine, your resting heart rate can be as high as 100. Your resting heart rate will also increase as you age, so you may have to repeat this step periodically.

This will establish a baseline and help you to determine if additional medical intervention is required before you start a new exercise program.

B. Know your target heart rate range.

For this step, you can use the age-based chart on the American Heart Association's website:

This step will be expanded in the intermediate step, below.

C. Monitor your exercise to make sure you're within your target range.

Then, as you exercise, monitor your heart rate. You can do this for free with a watch and your finger, but a much easier way is with your Garmin (or similar device). The point here is to keep your heart in the range indicated for your age.

I'm between 45 and 50, so my target heart rate is 88 to 149 beats per minute. This represents 50 to 85% of my maximum heart rate (estimated to be 175 beats per minute per this chart).

The point is to slow down if your heart rate goes over the maximum and to increase effort if your heart rate goes below the minimum. Start out slow and increase over time.
During the first few weeks of working out, aim for the lowest part of your target zone (50 percent). Then, gradually build up to the higher part (85 percent). After six months or more, you may be able to exercise comfortably at up to 85 percent of your maximum heart rate. But you don't have to exercise that hard to stay in shape.
Exercising in your target range will maximize fat burning and aerobic activity. You have to keep your heart rate up in the range from thirty minutes three times per week (for minimal results) up to at least one hour every day to achieve real weight loss.

II. Intermediate: Calculating your Maximum Heart Rate

Once you have a good handle on maintaining exercise in your target zone, you can fine-tune those numbers by calculating your personal maximum heart rate, rather than relying on the averages. There are several methods. I'll outline the first one here. Ride With GPS points to Sally Edwards's page on calculating heart rate, which is where I got this information.

The SubMax 1-Mile Walking Test.
Go to any high school or college track (most are 400 meters or 440 yards around) and walk or stride as fast as you can in your current condition. Walk as fast as is comfortable. Walk four continuous laps. 
The last lap is the important one. Take your pulse, or use your heart rate monitor, to determine your average heart rate for only the last lap. The first three laps are just to get you to reach a heart rate plateau and to stay there for the last lap. 
Add to this average last lap heart rate the one of the following that best matches your current fitness level: 
1. Poor Shape: +40 bpm 
2. Average Shape: +50 bpm 
3. Excellent Shape: +60 bpm
This final number (for example, an average 135 bpm last lap plus 60 bpm, because I'm in excellent shape, would equal 195 bpm for me) should be fairly close to your Max HR.

I haven't tried this yet. Anyone willing to do it with me?

III. Advanced: Training Zones

Since I've not even figured out my personal maximum heart rate, I can't say that I'm ready to talk about training zones with any authority. However, I'll lay them out here and leave it for future blog posts to discuss the details.

Basically, each "zone" is a subset of your target heart rate range, plus the range from 80 to 100%. A general description from Bike Radar is:

  • Zone 1 (60-65% of maximum heart rate): For long, easy rides, to improve the combustion and storage of fats.
  • Zone 2 (65-75% of MHR): The basic base training zone. Longish rides of medium stress.
  • Zone 3 (75-82% of MHR): For development of aerobic capacity and endurance with moderate volume at very controlled intensity.
  • Zone 4 (82-89% of MHR): For simulating pace when tapering for a race.
  • Zone 5 (89-94% of MHR): For raising anaerobic threshold. Good sessions for 10- and 25-mile time-trials.
  • Zone 6 (94-100% of MHR): For high-intensity interval training to increase maximum power and speed.

If you follow the AMA guidelines, you'll stay in Zones 1, 2, and 3 for your entire ride. As you can see, generally, this means burning fat and moderately intense exercise. For me, using 180 as my maximum heart rate, these zones are:

  • Zone 1: 108 to 117 bpm
  • Zone 2: 117 to 135 bpm
  • Zone 3: 135 to 147 bpm
  • Zone 4: 147 to 160 bpm
  • Zone 5: 160 to 169 bpm
  • Zone 6: 169 to 180 bpm

Now I know I ride over 147 bpm regularly. For my most recent 78 mile bike ride, I was in Zone 4 for only 11 minutes.

So, what are the advantages of training up to be in higher zones? Without reading more, I can say that training for higher zones increases your capacity to ride in them. This means that you can climb faster and more efficiently. Since climbing is my favorite part of cycling, I'm going to try to increase this number over time.

I'm also going to read more about how to do so, and will report what I learn here. Anyone want to go for a ride?

Your Bear

Thursday, July 18, 2013

Cycling for Fitness

I've been avidly cycling about 3 years now. I've ridden at least 18,083 miles since 2010 (11,102 on the odometer, and the rest estimated from non-odometer rides) — that's an average of about 115 miles per week. And that's nothing. Some of my friends report having ridden over 5,000 miles just in the first half of 2013 (Joseph Collins, you're my hero)!

I have only one explanation: cycling makes life worth living. It gives me energy; it makes me feel sexy fit and happy; it is good for the environment; and I get to do it with some amazing people. Because of cycling, I have friends all over California who I would otherwise never have met!

Matthew Inman has a 6-part series about why he runs which sums up his reasons in typical pithy Oatmeal fashion: he runs to eat. Though its a bit cynical, I have to say I agree with Matthew. I don't cycle because it will make me look sexy, but because it makes me feel sexy, which is just as important!

All this is to say, JOIN ME on the AIDS/LifeCycle 2014. If you do, I promise to help you get fit enough to complete all 545 miles!

Here's a snippet of the 6-part Oatmeal cartoon. Click the links or the image to read the whole thing (then buy something from his store).

Your Bear

Saturday, July 13, 2013

Heat Stroke: How to Cycle in Hot Weather

Daily temperatures in Sacramento rarely dip below 90º in July and August — an 80º day is considered chilly here. Recently we've have temperatures pushing 110º, a rarity for Sacramento, but not unheard of. I see a 10 to 15% degradation in my performance when the temperature is above 90. So I'm wondering if there's a way to really chip away at that degradation and get up to 100% even in the hea
t of the summer.

The question is, how do you maintain your training schedule in that heat? Its not easy! There are obvious tips that occur to me off the top of my head:

  • Ride early;
  • Ride at night;
  • Drink plenty of water and electrolytes;
  • Eat salty food;
  • Wear a hat under your helmet and wear plenty of sun screen; and
  • Practice, practice, practice! name a few. Conspicuously off the list is taking breaks, even in the shade. You'll see that moving is key to remaining cool while cycling on a hot day. And that's because moving makes you sweat.
According to the on-line magazine Active, there are four ways your body dissipates excess muscular heat, making prolonged summer cycling possible: "... conduction, convection, radiation and evaporation." Although the article doesn't come out and say it, sweating is the key to each of these. And that means two things: moving and hydration.

Moving increases your exposed skin, aiding radiation. Moving creates its own wind, aiding in evaporation. Moving brings hot fluids from your core to the outside, aiding conduction and convection. Most importantly, moving makes you sweat which then evaporates off your skin — and evaporation is the key to the process:
Sweat is mostly water, and molecules in water are in constant motion. The temperature of water gives us an idea of the average motion of the water molecules. Each water molecule bounces off its neighbors, sometimes gaining energy from the collision, and sometimes losing energy to other molecules. At any given time, however, some molecules carry more energy than others. That is, most molecules will have temperatures close to the average, but some will be much hotter or colder than the average on occasion. 
When water evaporates, some of the molecules fly out of the liquid into the air. Hotter molecules have more energy and are moving around faster, which means that they are more likely to fly away and leave the cooler molecules behind. The evaporating molecules in your sweat actually carry the heat of your body into the air. [From American Institute of Physics.]

The lesson is: taking a break may be necessary if you're fatigued, but its not going to cool you off on a hot day!

Hydration is equally important in this process: you can't sweat if you're dehydrated:
While sweating is necessary to help cool the body, the production of sweat comes at the expense of your body fluids. As much as 1 to 2 quarts of fluid per hour may be lost as sweat while cycling in very hot weather. To help you understand the seriousness of this, the loss of as little as 2 to 3 percent of your body weight due to dehydration can impair exercise performance. [From Active, p2 for additional tips.]
My large water bottles hold 25 oz. each. Since, according to this estimate, I'm losing 32 to 64 hours per hour, I have to drain both water bottle each hour I ride. That's a LOT more water than I usually drink!

So for me, for now, I'm going to try to drink a LOT more water on my hot-weather rides.

Your Bear

Thursday, July 4, 2013

Getting Back into the Groove

This is the time of year that is most difficult for me to get back on my bike. After a two-week
AIDS/LifeCycle and vacation break, I'm finding other things pulling my interest (not the least of which is work, since I didn't make a penny during my break). Plus its been hot in Sacramento. Today the high is supposed to be 108º F; the fifth day in a row of plus 100 degree temperatures. And for some reason, the humidity has been unusually high, too; right now its 35%.

I've not entirely abandoned cycling. Since June 17, when I got back, I've done three 35 mile rides plus I've ridden to the gym about 10 times (13 miles total each time). Still, it doesn't feel like enough. Especially given my goal to lose about 15 lbs before August (getting me down to 160 lbs).

So, I'm going to institute the following weekly summer regimen:

  1. Five days per week, ride my typical commute to the gym (65 miles).
  2. Two days per week, ride at least 35 mile (70 miles).
  3. At least one weekend ride of 35 miles with some hills (35 miles).
So the total minimum ride from July 1 to September 1, 2013 will be about 170 miles. Starting after the holiday weekend.

I want at least one of the rides in nos. 2 and 3 to be a group ride. So, I'm going to commit to doing two ART rides on Tuesday and Thursday afternoons from 5:00 p.m. to 7:00 p.m. (unless another commitment conflict). I'm putting them on my calendar now; join me.

I'm also going to commit to leading one local 30 to 50 mile ride every weekend starting on 7/13/13 until 9/1/13, or going on a ride in the Bay Area (a friend is OOC there and I may need to go on the spur of the moment).

I'll post both of these types of rides on the Sacrament ALC Training Ride page. Please like the page for more.

Your Bear