A couple of people were asking about the ithlete heart monitoring app so I thought the following might be useful:
Your heart rate and rhythm are mostly controlled by the autonomic nervous system which is split in to the parasympathetic nervous system (rest and digest) and the sympathetic nervous system (fight or flight).
The parasympathetic nervous system inhibits variations in the amount of time in between heart beats. The sympathetic nervous system increases variations. There are typically slight variations in heart rate when breathing in and breathing out, through temperature changes, blood pressure variations and stress.
Heart Rate Variability (HRV) is a measurement of these variations, typically measured on a scale of 0 to 100. The higher the HRV the better.
If you are well rested, not over trained, or haven’t been training excessively, the parasympathetic and sympathetic nervous systems interact cooperatively to produce well tuned responses to respiration, stress etc. This results in a higher HRV score.
If you are not well rested, over trained, or under recovered, the beat-to-beat variation begins to diminish, resulting in a lower HRV score.
Consistently high HRV scores translate to both healthy nervous systems and improved performances.
French and Australian researchers have found performance in weekly 400m swim time trial tests could be predicted from HRV with very high accuracy. (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0052636)
Research by Dr Martin Buchheit (Head of Performance at Paris Saint-Germain FC) also found that as HRV improves in runners, so does race performance.
There are various apps which measure HRV. I recommend ithlete (http://www.myithlete.com/). Another alternative is SweetBeat (http://sweetwaterhrv.com/).
Both need an appropriate sensor in addition to the app. I’ve found Bluetooth Smart Heart Rate Moniors to be the most reliable and cost effective. Neither are currently compatible with Garmin heart rate monitors, but you can find Bluetooth Smart straps on eBay or Amazon for under a tenner. I’ve been using ithlete for around 4 years and I absolutely swear by it.
The procedure is simple and takes about 60 seconds per day. On waking, you breathe in and out in time to the animation on the app. (Standing gives the most accurate reading as the parasympathetic nervous system is overactive when lying down). I do it as soon as I’ve gotten out of bad, just after I’ve been to the bathroom. When complete you are given your resting heart rate and HRV score for the day.
After a few days of use the scores will be coloured using a traffic light system. Green is good (relative to your recent scores). Orange caution. Red is bad. As well as using it as an indictor of performance you can also use it to help structure your training and recovery.
If on any given day you have a green score, you can train hard and safely. If the score is red, then rest may be more effective than training. (Regular overtraining can increase vulnerability to injury, lower testosterone levels in men, amenorrhea in women, mental stress and anxiety). Measuring HRV helps take the doubt out of whether listening to your body is necessary or if it’s just laziness.
Aerobic workouts such as long, slow runs, or Tristan’s CSS swim sets will typically result in consistent or improved HRV scores. After anaerobic (fast, high intensity) workouts the autonomic balance is slightly disturbed until the body recovers. After adequate recovery from orange HRV scores, a gradual increase in average HRV is often found. Over reaching, such as a too difficult training session or frequent over training in the orange zone, can see a decrease in HRV and frequent red scores or erratic readings. You are looking for a gentle upward progression. Measuring HRV can help check yo’self before you wreck yo’self (https://www.youtube.com/watch?v=bCY9L3Xidoo).
Alberto Salazar’s own training programme was so intense he developed chronic over training symptoms, including high blood pressure, a serious heart attack and permanently low testosterone. (This is one reason he uses a testosterone cream that was alleged he used on his athletes). Mark Allen’s coach Phil Maffetone uses the formula “Training = Work + Rest”.
Sometimes over training will show an initial improvement in HRV, which is why tapering before a race works. Other influences I’ve found are sleep quality, diet, hydration and general stress levels. Alcohol can have quite significant adverse effects. It will pick up on everything (apart from gin I've found!).
You might have noticed that you have a higher heart rate when you are ill. Once your pulse is raised above normal levels you are already suffering. A poor HRV score can be an early indicator so you can take steps to recover before the negative effects kick in.
An approximation of a HRV test is monitoring how long you can hold your breath for on a daily basis. If this time is significantly lower on a given day then this may equate to a poor HRV. ithlete gives you a bit more insight and you can log reading against training load, sleep quality, mood, and diet. After using it for a couple of weeks it becomes very intuitive and you can forget the theory and just go by colour.
I have nearly 1,500 consecutive days of HRV scores and would be happy to share the data. I’d also be interested in any results anyone else has with ithlete.
Cheers,
James
