Using HRV for Improved Sports Performance

Most athletes know that getting enough rest after exercise is essential to high-level performance, but many still over train and feel guilty when they take a day off. The body repairs and strengthens itself in the time between workouts, and continuous training can actually weaken the strongest athletes. In competitive sports, improved performance is achieved by alternating periods of intensive training with periods of relative rest. Rest is physically necessary so that the muscles can repair, rebuild and strengthen. For recreational athletes, building in rest days can help maintain a better balance between home, work and fitness goals.

While standardized training programs produce well documented results, they do not take individual responses into account. Age, gender, race, baseline fitness level, and genetic factors are known determinants of individual differences in responses to endurance training. In addition the status of the nervous system plays an important role in training response.

Heart Rate Variability (HRV) is a view into the nervous system and can be used to guide an optimal training program. Never heard of the term? You are not alone. Measuring HRV, though long used in hospitals for treating heart patients, is a relatively new biofeedback concept for endurance athletes. Soviet Union sports scientists started keeping track of their elite athletes’ HRV in the ‘70s. In the past decade, college sports teams and world-class athletes have been increasingly using HRV to monitor fatigue and recovery from workouts. There are numerous clinical studies on HRV and training.

The introduction of athletic heart rate monitors that communicate with smart phones has enabled HRV monitoring capability to anyone who has a smart phone and wants to use it to guide training.

SweetBeat is an iPhone app by SweetWater Health that has custom capability for athletes to track their HRV. The athlete simply does a 3 minute HRV session each morning and is presented with a result that recommends “train as usual”, “low exertion day” or “rest day” based on the individual’s baseline trend. New SweetBeat updates include power frequency graphs and audio alerts.

The new SweetBeat power frequency graphs display the LF (low frequency) and HF (high frequency) components of HRV. LF and HF are bands of the HRV power spectrum.  The LF power level represents both branches of the nervous system, the sympathetic (fight or flight) and parasympathetic (rest and recovery).  The HF power level is a reflection of the parasympathetic branch of the nervous system, and responds quickly to rest and recovery.  Both LF and HF are expressions of overall fitness and resilience.  These power levels are relatively high when the nervous system is active and flexible.  Typically, these power levels range from 800 to 1000 for fitness enthusiasts and 6000-8000 for elite athletes as measured in the SweetBeat application. This feature provides important additional information about the nervous system and fitness levels. Tri-athletes and more advanced users have requested this feature. Along with a graph representing the power frequencies over time, a real time graph will show your power for each session.

Good luck with your training! If you have any questions you can email us at and we will reply within 24 hours. Don’t have SweetBeat, yet? Download SweetBeat on iTunes now!


Customize SweetBeat to Suit Yourself

You can customize SweetBeat to fit your personality and stress sensitivity. You can also make each session more meaningful by noting your current mood and activity. When you look at your sessions online in MySweetBeat , you will be able to compare your HRV and stress levels while you were commuting to work, for example, compared to sessions recorded while exercising or playing with your kids. Information about how your body responds is the first step toward making positive changes.

Download SweetBeat™ for the iPhone to monitor your heart rate variability (HRV) and learn how to detect and manage stress.

How Stress Changes Our Bodies

Stress is not caused exclusively by what happens to us; sometimes our thoughts and emotions are more culpable in producing stress than anything external. Stress—however it is produced—can cause massive physical changes in the body. Human beings evolved in an environment where failure to respond instantly to a threat often resulted in death.  When we perceive a threat, the body floods with stress hormones like adrenalin that accelerate the body’s ability to respond rapidly. Heart rate and breathing increase, muscles tense, we sweat more, and non-essential functions shut down as the body goes into “fight or flight” mode to deal with the danger. Can you recall an incident that produced this kind of reaction in your body—even when your life was not at risk?

Download SweetBeat™ for the iPhone to monitor your heart rate variability (HRV) and learn how to detect and manage stress.

Anyone Can Beat Stress

Sometimes the simplest answer is the best answer. Years of research have shown that deep, regular breathing can reduce stress by balancing the nervous system. SweetBeat™ has a “Relax” screen that helps you to beat stress by helping you to time your breathing while gazing at a relaxing image. You can even use your own relaxing images! (Photos of kittens and puppies work for us.)

Download SweetBeat™ for the iPhone to monitor your heart rate variability (HRV) and learn how to detect and manage stress.

Use SweetBeat for More Effective Workouts

SweetBeat™ can be used to make your workouts more effective. When your body is stressed or at a low point physically, your heart rate variability (HRV) level will be lower, too. Following a “canned” training routine may cause yet more stress and damage under these circumstances. If your HRV is low, switch to a less-strenuous workout and save the tough stuff for a day when your HRV is higher.

Download SweetBeat™ for the iPhone to monitor your heart rate variability (HRV) and learn how to create a more effective training routine.

Good Stress and Bad Stress

Stress affects the nervous system. What kind of stress are we talking about?

All sorts of things can cause stress, from physical exertion to a bad day at work. There’s  “good” stress (like receiving a big promotion), and there’s “bad” stress (like having a traffic accident). But when we talk about stress in this blog, we’re talking about bad stress—the kind of stress that can damage your health and happiness.

Download SweetBeat™ for the iPhone to monitor your heart rate variability (HRV) and learn how to reduce stress.

SweetBeat Tools for Better Health

SweetBeat™ is more than just a cool app on your iPhone. SweetWater Health has created ways for you to chart your SweetBeat sessions, track sessions on a calendar, compare sessions by time of day, day of the week, and more. Register at MySweetBeat to see how you can manage your health more effectively with SweetBeat tools.

Download SweetBeat™ for the iPhone to monitor your heart rate variability (HRV) and learn how to create a more effective training routine.

SweetBeat App for Stress and Fitness Management Available Now!

We’ve talked about monitoring heart rate variability (HRV) to balance your nervous system and manage stress. Now SweetWater Health is proud to announce that you can monitor your HRV accurately, non-intrusively, and easily with our SweetBeat™ iPhone app!

Here’s our press release with more info:

Easy-To-Use Mobile Health App Launched

by SweetWater Health

SweetBeat App Based on 30 Years of Clinical Research

February 6, 2012—Los Gatos, CA—SweetBeat™, a new iPhone application, helps users to effectively manage fitness and stress using simple, easy-to use methods accessible to everyone. SweetBeat by SweetWater Health™ LLC is available now from the Apple iTunes Store for $1.99. Future versions will be compatible with Android phones.

Whether the user is a dedicated athlete, yoga enthusiast or just someone concerned about health, understanding how the body reacts to stress allows people to optimize their lives for maximum effectiveness. For fitness enthusiasts, SweetBeat is a simple application that allows users to plan workouts based on vital signs, rather than a canned workout schedule. For people with busy, stressful lives, SweetBeat is an easy way to measure and manage stress levels throughout the day.

How SweetBeat Works

Using one of several compatible and affordable heart rate monitors, SweetBeat measures the user’s heart rate variability, or HRV, which has been researched for about 30 years. HRV is the variation in the time between heartbeats. Clinical studies have shown that when a person’s stress rises, HRV falls (the interval between beats becomes more regular). The less stressed the person is, the higher the HRV level (the interval between beats becomes less regular).

With SweetBeat, users can see their HRV levels in real time, giving them the ability to take action to manage stress or vary their workouts. When a user’s stress rises above the user-determined threshold, a “Relax” screen appears with a breath pacer. Simply by breathing deeply and regularly, the user can balance his or her system, returning to a more relaxed state.

In competitive sports, improved performance is often affected by alternating periods of intensive training with periods of relative rest. Clinical studies have shown that HRV is an effective metric for detecting overtraining. SweetBeat measures HRV and provides an objective measure of your body’s response to each workout.

SweetBeat sessions can be uploaded to SweetWater Health’s secure database, enabling users to access their data at “MySweetBeat,” either through the iPhone or on the SweetWater Health website. In MySweetBeat, users sign in securely to see a calendar of their sessions, color-coded by average stress level, and session summaries. They can also chart their sessions in a variety of ways, comparing readings for different times of day or from day to day, for instance. If they want, users can share their SweetBeat results with friends via Twitter or Facebook.

SweetBeat can be used to “spot-check” for stress. However, the app can also be used to record lengthy sessions if desired, allowing users to view how readings shift during an extended period, or during exercise.

Product Features

Personalization: SweetBeat offers a number of user-friendly features to make SweetBeat both intuitive and fun. Users can provide the app with information about themselves by recording a baseline session (this isn’t mandatory, but does result in more accurate readings). Users can select among 26 “Persona” that describe their personal traits such as “Active,” “Spiritual,” or “Home Body,” and record gender and age

Users can set their current perceived stress levels at any time during a session, and they can select from 12 different states, from “Nervous” or “Happy” to “Working” or “Partying.”

Users can also personalize the Relax screen graphic. The default graphic is a fractal image that shifts from edgy red to cool blues and greens as stress levels fall, but users can select up to five of their own stress-reducing images.

Monitor Screen: The Monitor screen shows the user’s heartbeats in a familiar, EKG-like animation. Dynamic windows show the heart rate, detected stress level, and HRV level.

Breath Pacer: The Breath Pacer screen is designed to guide users through a relaxation session if SweetBeat detects high stress. The screen features a default image that changes as the user becomes relaxed—or users can select their own soothing images. There is also a visual and auditory cue that helps users to breathe deeply and rhythmically, a process known to balance the nervous system and return the body to a state of relaxation

Sensitivity Settings: Everyone has different levels of sensitivity to stress and exercise, so SweetBeat allows users to determine which level to use. People who are naturally high-strung may want to set the app at Level 1 (the least sensitive) to get a meaningful reading, while a more mellow type might use Level 5 (the highest sensitivity to stress). SweetBeat users may find they become less sensitive to stress over time; the app allows raising or lowering sensitivity settings as needed. Users can set the threshold of stress at which the Breath Pacer will appear to help them relax, and they can turn Stress Alerts on or off. Users can also set their Heart Rate Thresholds and turn Heart Rate Alerts on or off.

About SweetWater Health, LLC:

SweetWater Health™ is revolutionizing mobile health monitoring and stress management by combining proven medical research techniques with the latest mobile computing technological advances.

SweetWater Health, located in Los Gatos, CA, was founded by Ronda Collier, who researched HRV and stress for three years before beginning product development on SweetBeat. She and her partners, Donna Leever and Jo Beth Dow, are Silicon Valley veterans with deep experience in technology and the successful launch of high-tech startups.

Digital Press Kit