Heart Rate Training For Triathlon
(Central Coast, NSW Australia)
As a beginner triathlete but long time recreational athlete (Surfing, mountain biking etc), I am wondering how to best utilize my Heart rate monitor.
I want to know the best way to determine my heart rate zones (LT1, LT2, endurance, VO2 Max, etc) without needing expensive testing. Then once I know these, how much time should I spend in each zone? How often should I retest myself to update my HR zones or will they stay constant?
Intelligent Triathlon Training replies:
Heart rate zones stay fairly fixed and are generally speaking not dependant upon fitness. If you are completely non-trained and undertake a long-term programme of several years then you would expect to see a slight rising of LT1 and 2 but not max.
If you are mildly trained and undertake a sustained programme there will be minor changes, but to all intents and purpose they don't change much. What you will see is that you can do more work at the same heart rate as your training progresses - ie run faster, or produce more power on the bike.
Age is the other thing that will change heart rate training zones as your maximal heart rate decreases with age. But over the period of 1-5 years you will not see a noticeable shift.
If you only want training zones, don't bother with testing as it's an expensive way of getting some mildly accurate information. One of the reason heart rate zones have a range is because heart rate isn't predictable day to day! It will reduce slightly with fatigue, or this could also cause it to rise. Different things cause the heart's pacemaker to vary slightly.
Over time you may come to recognise the reasons yours changes slightly such as an oncoming illness or fatigue, or being well recovered, and tweak your training to reflect this.
For instance, one of our squad was recently doing a rollers session. He was struggling to get his heart rate up and was finding it difficult to achieve power outputs of which he would normally be capable. All these factors suggested something was not right. He said he felt fine, but agreed to stop the session. 2 days later he was bed ridden with the flu.
The underlying symptoms were there and because we were doing such a specific session with both heart rate and power (although either one would have been sufficient to realise something was not quite right) we were able to catch it quick and not let him dig a big hole of fatigue and make it worse.
How you use zones and how long you spend in each will really depend on what you are training for, which stage of your training you are in and how much training you are doing.
For example if you were training for an Ironman you would spend a lot of time in the easy or steady training zones. If you were training for a sprint triathlon you would spend some time in these zones, but relatively more in the higher intensity zones.
If you were doing an extensive endurance session then the majority of the run/bike needs to be in the STEADY zone (75-90% depending upon terrain).
If you were doing a TEMPO run then during the tempo part all of the data should be in your tempo zone.
The thing to remember is that HR can be slow to respond, so you may accelerate and be going quite hard but HR will lag behind, so it is unreliable in short intervals of less than 2-3min. You can use final heart rate in those sort of sessions but with reps of less than 60-90s even final HR won't really reflect your work rate.
Repeated intervals with short recovery may be slightly more accurate, say 10x1-min with 30s recovery, as HR will also be slow to descend (relatively speaking; it certainly won't reflect the work you are doing at that moment in time, i.e. the recovery).
The information below shows how to work out the zones, although these are guidelines. Remember there may be a difference between bike and run.
MHR = max heart rate
To get your MHR find a decent hill of about 4-5min long and ride up it as hard as you can for that duration. For running, do a 5 -7min rep as fast as you can or 3 x 3min with 45s recovery between. Start hard, and get harder on each rep, the last rep should be flat out! .
Very hard 92-97% MHR
HARD 86-91% MHR (Top end of this is LT2 and is your 1hr bike TT heart rate.)
STEADY 68-79% MHR (Top end of this should be sustainable on a bike for 90min+, more if well trained, and is ~ LT1)
Easy < 68% MHR