Ask Ann: Heart Rate Homework, Part 2

Ann Trason

Last month I described some fun ways to get to know your new training partner, your heart rate monitor! The goal this month is to let your training partner explore ways to elevate your training and racing to the next level.

Wake Up Heart Rate

Over the course of the last month, I hope you’ve had time to chart your resting heart rate. By knowing your resting heart rate, you will be able to get a head’s up from your body on injury, illness, overtraining, stress and incomplete recovery. A big red flag would be if you see a jump of more than 10-15% in your resting beats per minute.

If your resting heart rate is waving a red flag, it’s time to listen to your training partner by checking in with your hydration levels and possibly adjust your training schedule. Take the extra steps to get plenty of fluids and to eat healthily. This is a good time to hit that bathroom scale and check your body weight. Most likely you have dropped some weight from the previous day. According to a study reported in the Journal of Physiology (Joyner, et al., 2003) “mild exercise-induced dehydration causes an increase in resting HR.” One of my ultrarunning commandments is: “never underestimate the healing power of good old-fashioned water.”

The red flag enlarges in size as your resting heart rate stays elevated over consecutive days. Your training partner is now telling you to allow some time for injury assessment while stretching and warming up on your runs. If you do not detect an injury or illness, overtraining may be the cause of the increase in your resting heart rate. At this point, adding in additional rest days, and getting more sleep are the smartest choices you can make.

On the other hand, if your resting heart rate is decreasing as your training progresses, you and your training partner should be happy with these results! You are increasing your fitness level. Hearts are muscles that get stronger with training. As your heart becomes stronger and more efficient, it will not need to beat as many times per minute to circulate your blood. Yup, your heart, is getting more economical!

Staying In The Zone

Another part of your homework last month was doing the math on your maximum heart rate. Once you know your MHR, I suggest using the following heart rate zones from Sally Edward’s book, Smart Heart.

Zone 1. Healthy Heart (Aka Chill Zone)

  • 50-60% of max heart rate.
  • Recovery runs, warm-up, cool down from harder workouts.

Zone 2. Temperate Zone (Aka Ultra Zone)

  • 60-70% of max heart rate.
  • Fat is used as primary fuel source.
  • It is good to do early season/base building long runs in this zone.

Zone 3. The Aerobic Zone (Aka Most Bang For Your Buck Zone)

  • 70-80% of max heart rate. You should be able to carry on a conversation in this zone.
  • Fuels burned are roughly: 60% carbs, 40% fat.
  • Major adaptive physiological changes take place in terms of metabolism, skeletal muscles and heart muscle when runs of this profile are included into your training regimen.

Zone 4. The Threshold Zone (Aka Tempo/Long Interval Zone)

  • 80-90% of max heart rate.
  • This is the last aerobic zone before crossing over to the anaerobic threshold.
  • Carbohydrates are used predominately for energy.
  • Most tempo runs are done in this zone. Only one of these workouts per week should be included in your training. Sixty to 90 minutes maximum.
  • Utilizes both aerobic and anaerobic pathways, stimulating favorable adaptations.
  • Too much in this zone can lead to injuries.
  • Not for the weak of heart.

Zone 5. (Aka Red Zone)

  • 90-100% of max heart rate.
  • Short sprint intervals, i.e. speed work.
  • It is recommended to spend equal amounts of time resting and exercising in this zone.
  • This is the top of the heart rate chain and leaves you gasping for air.
  • As I get older running to catch a bus is the only time I enter this zone!

As you discover what works for you, keep in mind that:

One of the most common mistakes is to run your easy days way too hard. Let your heart rate monitor/dictate these days for you and stick to them. It is during the recovery phase of your training that your fitness increases.

During a hard work out day, collaborate with your heart rate monitor and zones ahead of time, i.e. establish your targets and limits before the workout begins. However, for hill repeats and speed workouts, you do not need to check your monitor repeatedly. Concentrate on the task at hand and get your workout done!

Once you get home, it’s important to analyze your data, but think of the numbers more as discussion points and feedback rather than the ultimate truth.

Try to stay away from Zone 4 for prolonged periods of time during an ultra event, especially if it is hot or a 100 miler.

Remember that cardiac creep is normal while racing. Dehydration is the main culprit.

Heart rate zones do change with conditioning and improved fitness. The better shape you get in, you will notice beats per minute (bpm) to reach Zones 4 and 5, for example. This is a good thing, as your A race goal is to be able to sustain the highest heart rate possible for a given event.

The ultimate goal is that your training partner does not need to join you for all your runs. After checking in with your resting heart rate in the morning, eventually you will come to know what your heart rate is during any given time just by feel!

Since my last column about Heart Rate Monitors, friends have been asking me about my personal experience with this. Here’s what worked for me during my racing in the mid 1990s:

  • Knowing my numbers and checking in with them !
  • Resting heart rate was low to mid 30s.
  • Maximum heart rate was 187.
  • Easy running was around 120 to 135 bpm.
  • Tempo runs were done around 150 to 160 bpm early in the training cycle, then rose to around 170 as racing season kicked in.
  • Long runs were done around 135 to 150 bpm.
  • Speed work was done around 180 bpm.

For easy runs, using the heart rate monitor kept me honest and stopped me from running too hard. For long runs, the heart rate monitor kept me running at an even pace and helped me last longer out there, and really stimulate fat metabolism for fuel.

For tempo runs, using the heart rate monitor kept me in the right Zone. As I became more fit I would see my heart rate in zone 4 getting closer to my max HR.

When it came to race day, the heart rate monitor was a tool that I always started out with to keep me at an even pace. For example, I ran Comrades Marathon at 155 bpm. However, usually about halfway through every race, I reached a point where I decided to let the heart monitor go. This is when I would say goodbye to my training partner, and go forward on my own, into the abyss…

I wish you the best as you get to know your training partner. Whether your goals are to run five milers around your neighborhood, or to train for your first ultramarathon, using a heart rate monitor can provide important feedback as you progress.

Good luck with your training and keep your excellent questions coming to me: askann@ultrarunning. com!


The following two tabs change content below.

Ann Trason

Ann Trason is a 14-time women’s champion at the Western States 100, and set World Records at the 50-mile (5:40:18 in 1991), 100K (7:00:47, 1995), 12-Hour (91 miles 1312 yards, 1991) and 100-mile (13:47:42, 1991) distances. Ann was co- director of the Firetrails 50 in northern California for 10 years, and has taught science at the college level. Ann currently coaches middle school cross country and supports other's ultrarunning achievements by volunteering, pacing and crewing at ultramarathon races throughout the Western US.

Latest posts by Ann Trason (see all)

  • allanholtz

    Can one use a heart rate monitor to monitor resistance training (weight lifting)? I do not think it adequately measures the effort expended in such training.

  • allanholtz

    Interesting numbers Ann from your mid 1990’s. What would your heart rate numbers – resting, easy running, 5k racing and ultra target heart rates look like now?

  • allanholtz

    I still enjoy analyzing my heart rate data from 100-mile races.