How To (Properly) Calculate Your Target Heart Rate Zone

Monitoring our heart rate during exercise is an excellent way to determine and quantify the intensity of our workout. But what intensity should we be working out at and what is the best way to calculate this? The traditional method of calculating your target heart rate (Percentage of Predicted Maximum Heart Rate) factors in only your age (Predicted Max HR = 220 - Age). For example, world-class ultramarathoner Scott Jurek is 46 years old and therefore has a predicted maximum heart rate of 174 beats per minute (bpm). While using this traditional method, most recommend a target heart rate zone (the zone you want your heart rate in during exercise) to fall between 50-85% of your maximum heart rate. For Scott Jurek, we find his target heart rate zone to be roughly 87-148 bpm. The benefit of this method lies in the simplicity of the calculation. However, there are shortfalls of utilizing this method to calculate target heart rate zones. First, the range of this target heart rate zone is much too large and subsequently not very prescriptive. Second, the low end of this target heart rate zone may not be attainable during exercise, especially in older adults with higher resting heart rates. For example, the predicted maximum heart rate for a 75 year old woman is 145 bpm. Let’s assume this individual has a resting heart rate of 75, which is fairly typical. Utilizing the traditional method results in a calculated target heart rate zone of 73-124 bpm. As you can see, her resting heart rate is higher than the low end of her target heart rate zone for exercise. Therefore, the percentage maximum heart rate method of calculating her target heart rate zone would say she is exercising at rest, which is nonsensical. In other words, the traditional method often prescribes heart rates that are too low when working out at lower intensities, especially in older adults. Third, the traditional method fails to factor in your level of fitness, thus overly simplifying exercise prescription for a variable population. Since the traditional method of calculating your target heart rate fails to factor in your resting heart rate, it will prescribe the same target heart rate zone for Scott Jurek as an age-matched couch potato who smokes two packs per day. You see, as you become more fit, your resting heart rate will decrease as your heart becomes stronger and subsequently more efficient at pumping blood to the rest of your body. A highly trained athlete may have a resting heart rate of 48 bpm while the sedentary smoker may have a resting heart rate of 88 bpm. If they are both 40 years old, the traditional method of calculating target heart rate would recommend exercising between 90 and 153 bpm for both individuals. The traditional method therefore lacks this level of specificity.

So what is a better way to calculate your target heart rate zone? The answer is using the Karvonen method, otherwise known as the Heart Rate Reserve (HRR) method. The Karvonen method factors in both your age and resting heart rate, allowing for a more precise and effective target heart rate zone. The low end of the target heart rate zone tends to be at a higher heart rate than the traditional method of calculating target heart rate zones, while the predicted maximum heart rate is still the same. Those with a higher resting heart rate will see a higher number at the low end of the target heart rate zone as compared to those with a lower resting heart rate, to account for variability in the baseline levels of cardiovascular fitness within the population. Click on the link below to calculate your target heart rate zone using the Karvonen method:

TARGET HEART RATE CALCULATOR

Once calculated, it is recommended that you use this target heart rate zone to monitor your intensity during your workouts, in order to ensure that you are exercising at an intensity high enough to provide a cardiovascular benefit. This will help you get the most out of your exercise routine moving forward.

To find more information on heart rate or how to find your pulse, CLICK HERE.

-Grant Hennington, DPT

Quick Tips To Avoid Over-Training

Who out there is currently training for an endurance race or athletic event? For those of you who are, are you battling any nagging aches and pains? Unfortunately, both competitive and recreational athletes are subject to injury and it is well established that the majority of symptoms related to your training program are most likely the result of over-training. Think of over-training as being synonymous with overuse, and overuse described as repetitive and excessive microtrauma that overloads various musculoskeletal tissues. More simply, tissue breakdown exceeds tissue repair, leading to injury. With respect to endurance sports such as running or cycling, over-training can include excessive mileage, a rapid change in intensity/pace, and/or a sudden increase overall training distance. In other words, too much, too soon, too fast. A recent study reported that approximately one-third of runners with injuries described that they had changed their running routines just prior to their injury development. Another study demonstrated that injured runners had an average progression in weekly distance prior to injury of 31%, whereas the non-injured controls had a progression of 22%.

So what can we do to minimize our risk of injury while progressing through a training program? Here are a few tips:

• Progress slowly

  • As touched on, the majority of overuse injuries follow sudden or significant increases in duration or intensity. When participating in endurance sports, such as running or cycling, we want to follow the 10% rule, which states that we should not increase our weekly training mileage by more than 10% week-to-week. For example, if I run 20 miles this week, next week I should run no more than 22 miles in order to minimize my risk of injury while still adding mileage.

• Listen to your body

  • Think of pain as an alarm system within our body, alerting us of a potential injury to our tissues. Pain experienced in conjunction with your training program could be your body’s way of warning you of an impending injury if you continue to push it. Avoid taking medications like ibuprofen before a training run or workout, as to not impact your body’s ability to alert you of the need to stop.

• Mix it up

  • Many individuals focus on training for their primary sport nearly every day per week. This behavior stresses the same tissues in the same way day-in and day-out, leading to an increased risk of injury. Solution? Try participating in other physical activities or sports one to two days per week. For example, if you are a runner, try going cycling in order to get your cardio for the day. Or if you are a rock climber, take a day off and go to a yoga class. The key is using your body in a different way than you do in your typical training program.

• Take a break

  • While this is somewhat obvious, many of us are guilty of burying our heads in the sand and bucking this recommendation. Rest is important in both injury prevention and performance. Well rested tissues will function better than chronically overused tissues.

• Cool off

  • Applying a cold pack to a region of the body that is hurting after an intense workout can be an effective way to reduce or eliminate discomfort. This is a much safer long-term alternative to popping ibuprofen each and every day.

Happy training!

-Grant Hennington, DPT

Flexibility 101: Static vs. Dynamic Stretching

Have you ever wondered when you should be stretching with respect to your running program? More specifically, have you ever wondered what type of stretching you should be doing? While the research on stretching is a bit of a mixed bag, there are some tried-and-true principles to follow in book-ending your training runs, no matter your experience level within the sport.

Prior to running, we want to avoid static stretching, focusing rather on dynamic movements/stretches to warm up and prepare our muscles for the rigors of running. Static stretching has been shown to temporarily reduce the power output of our muscles, something we do not want to do prior to a run, as a reduced power output may make us slower. In contrast, a dynamic warm-up activates key muscle groups utilized during the running cycle in order to prepare those very muscles for sustained work. It is important that the dynamic warm-up closely mirror the physical demands of running in order to prepare the most appropriate muscles and tissues. In other words, performing walking lunges and skipping motions would be more appropriate than hitting a heavy bag. Finally, the dynamic warm-up should be simple and concise, requiring no greater than 5-10 minutes to complete. If longer or more complex, it is more likely you will skip it! Here is a sample dynamic warm-up routine:

Dynamic Running Warm-Up

Following your run, it is safe and appropriate to perform a static stretching routine, targeting the muscles and joints you stressed during your training run. Static stretching should be gentle and prolonged, holding each position for approximately 60 seconds. More aggressive stretching is not more effective, as it can more easily activate the stretch receptors in our muscles and tendons, limiting the ability for the muscles to relax and let go. Aggressive stretching also increases our risk of over-stretching and subsequently injuring our soft tissues. So keep it light! Key muscle groups to stretch following a run are the calves, hamstrings, quadriceps, and gluteals, all of which are primary movers during the running cycle. Here is a sample static stretching routine:

Static Stretching Cool-Down

Both routines should be easy and pain free. If you are experiencing discomfort with any of the positions, stop and move on. If possible, consult with a physical therapist or other medical professional if you have any questions or concerns regarding your specific stretching routine.

RUN ON!

-Grant Hennington, DPT

Foam Rolling 101 for Endurance Athletes

Have you ever been told you need to foam roll as part of your training program? If so, did you know why you were foam rolling or how you were supposed to go about doing it? Here is a quick Q&A guide to those interested in a simple and effective training tool.

What is foam rolling?

Foam rolling is a common form of self-myofascial release most often used by endurance athletes to help combat delayed onset muscle soreness (DOMS).

What are the benefits of foam rolling?

While foam rolling is most often used to treat muscle soreness and enhance recovery following intense bouts of exercise, foam rolling has also been shown to be an effective tool for improving joint range of motion at the hip, knee, and ankle without compromising muscle performance. Therefore, it can be beneficial when used either pre or post-workout. You will often see foam rolling utilized as a therapeutic tool used to treat Patellofemoral Pain Syndrome (i.e. runner’s knee), IT Band Syndrome, Achilles Tendintis, and Medial Tibial Stress Syndrome (i.e. shin splints).

What areas should I focus on?

Targeting sore areas of the muscles in the legs following a training session can be an effective way to enhance muscle recovery and reduce the negative effects of DOMS. Common regions to foam roll in the legs are the calves, hamstrings, gluteals, quadriceps, IT bands, and adductors. Here is a video of a sample foam rolling routine for runners:

What areas should I avoid?

In general, foam rolling is limited to soft tissue, as it is a self-myofascial release tool. Avoid rolling over bony prominences (bumps) or joint surfaces, as this is more likely to be aggravating as opposed to therapeutic.

How long should I foam roll each region?

Studies suggest that foam rolling an area for 30-60 seconds is sufficient to enhance joint flexibility and reduce muscle soreness. No need to roll much longer!

Other considerations...

Foam rolling is meant to be a tool utilized in conjunction with, not a substitute for, other evidence-based training principles. It will not eliminate your risk of getting injured if you are over-training or training inconsistently. As always, please consult your primary care provider or physical therapist if you have any questions or concerns before implementing a new wrinkle to your exercise routine, such as foam rolling. If you experience any progressive increase in pain or discomfort with foam rolling, stop and seek guidance from a healthcare provider or fitness professional.

-Grant Hennington, DPT

A Quick Guide To Selecting The Proper Saddle Height On Your Bicycle

With summer right around the corner, many of you are likely hitting the road and/or trails more often on your bicycles. Whether you are training for the STP Ride, commute to work, or enjoy a leisurely ride with friends, it is important to make sure you bicycle is properly fit to you, especially if you are starting to ride more frequently. There are five main connection points between you and your bicycle, all of which help determine a proper fit: two on the handlebars, two on the pedals, and one on the saddle (or bike seat). Selecting the proper saddle height is a basic adjustment even the most novice of riders can make. In general, your knee should be bent to about 30 degrees when your foot is at the bottom of the pedal stroke while riding (6 o’clock position). To the untrained eye, this can be difficult to estimate or measure without the proper tools. However, there is a way to get darn close by a technique called the “Heel Scrape Test”. The “Heel Scrape Test” is performed by setting a saddle height that allows your heel to barely touch the pedal when the crank arm is in the 6 o’clock position (bottom of the pedal stroke). Once in this position, your knee will end up in roughly a 30 degree angle when you place the ball of your foot on the pedal, which is the ideal foot position. No fancy digital software or goniometers necessary. Try it yourself and see how it feels on your next ride!

-Grant Hennington, DPT