WORKOUT WEDNESDAY INTERVALS

Join the Zwift Runners for a group run workout that will be of benefit to all distance runners.

Please read the event notes for this run carefully to gain maximum benefit. If you have any questions please post in the Zwift Runners Facebook group.

This week we will doing a Lactate Threshold test with the option of carrying on to also doing a max heart rate test as well. Lactate threshold is a key metric for a runner to know as it is the point where blood lactate increases markedly for small increases in effort. In simple terms no runner can run for long much past threshold and if you go past it too early in a distance race it rarely turns out well! However the nearer you can push your threshold heart rate up towards your max the faster you will likely go in races. Doing "threshold" and interval runs around this level will help to get used to that effort but first you need to know roughly what it is. In a lab threshold test actual blood samples can be taken. In Zwift of course we can't so will do our test based on the Conconi test which was outlined in a 1996 research paper following an initial 1982 paper.

The test will consist of a heavily progressive run that starts off at a very easy pace and increases 0.1 kph every 30 seconds up to a point a bit past where lactate threshold is likely to be for the group you join. If you manage to complete that stage you can optionally carry on to do the max heart rate test but then you need to increase your pace 1.0 kph every 30 secs until you feel you cannot go any faster and then need to stop the test. As such this stage of the test won't last more than a few minutes for anybody.

You will need to pair a HR monitor to Zwift for your threshold to be determined and we also recommend that you haven't done a hard run the day before as being tired can distort the results.

Please pick the pace group where you feel the final threshold test pace is hard for you but manageable. Once you have completed the threshold pace increases and optionally the final max HR increases then please ease off right and run/walk easy for a warm down until you have completed the set total distance. Please also note that there is no need to complete all the planned threshold pace increases. If you find you cannot raise your pace any more please ease right back and commence your warm down.

After you have completed the run you can post a link to your Strava (or similar) activity in the Zwift Runners FB group and we will try and work out what your threshold heart rate and pace is and discuss what then to do with the information. In simple terms, we will be looking for your "deflection point". This is where, if you plot HR against pace, the relationship ceases to be a straight line.

GROUP A 8.1K
Start at 10.0 kph (6.2 mph), increase the pace 0.1 kph every 30 seconds until you either feel that you cannot increase the pace any more or you reach 16.0 kph (9.9 mph). You can then optionally increase the pace 1.0 kph every 30 seconds until you are ready to stop the test.
Once the test is complete walk/run easy until you have completed the total distance.

Note that if you and/or your treadmill only works in mph then we recommend increasing pace 0.1 mph every minute but every 5 minutes increase 0.2 mph instead of 0.1 mph. The max heart rate test increases are 0.6 mph.

GROUP B 6.5K
As group A but the start pace is 9.0 kph (5.6 mph) and the final 0.1 kph increase is to 14.0 kph (8.7 mph).

GROUP C 4.6K
As group A but the start pace is 8.0 kph (5.0 mph) and the final 0.1 kph increase is to 12.0 kph (7.5 mph).

GROUP D 3.2K
As group A but the start pace is 7.0 kph (4.3 mph) and the final 0.1 kph increase is to 10.0 kph (6.2 mph).