Now the TRIMP zone method is a variation of Banisters' method, and this method was a effort to overcome the weakness of Banisters' strategy. The first step of the TRIMP zone method is to convert heart rate into one of five different zones based on the percentage of the athlete's maximum heart rate. And it's according to this chart. And I've got zones 1 through 5 listed there. Zone 1 is 50 to 60% of maximum heart rate. Zone 2 is 60 to 70% of the maximum heart rate, and so on. I've listed the other zones and their associated heart rates on this chart. The heart rate zone number replaces the raw heart rate data when calculating the TRIMP score. That is, TRIMP is equal to training time in minutes times the heart rate zone, in this case. For example, let's assume an athlete's maximum heart rate is 185 beats per minute, and this athlete completes two training sessions. So let's go through the data for both of these sessions. In session 1, the training time is 30 minutes at 140 beats per minutes average heart rate. Now, remember, the athlete's maximum heart rate is 185. Therefore their percent of maximum heart rate that they're working out in a session is equal to 140 divided by 185 times 100 and that gives you 76%. Therefore, the heart rate zone number is equal to 3. If you go to the chart where the athlete is working out between 70 to 80%, that is zone 3. And that is equal to 30 minutes times 3, which is the zone number, and that's equal to 90 units. So that's the TRIMP score for the first training session. So now let's take a look at session 2. The training time in session 2 is 25 minutes, and they completed this with an average heart rate of 180 beats per minute. Now their maximum heart rate is still 185 beats per minute, remember. So their percentage of maximum heart rate is equal to 180 divided by 185, which is their maximum heart rate. And that is multiplied by 100, and that gives you 97%. Therefore, the heart rate zone number, if you go to the chart, is 5. So the TRIMP is equal to 25 minutes times the heart rate zone number of 5. So that equals 25 minutes x 5, and that's 125 units. When comparing training session 1 with training session 2, it becomes quite clear that session 2 is a higher workload than session 1. That is, training for 25 minutes in a heart rate zone of 5 results in a higher TRIMP score than training for 30 minutes in a heart rate zone of 3. And in this way, it is possible to compare the stimulus loads for many different training sessions. Now this method is especially useful for calculating the TRIMP of an interval training session. Because interval training sessions are all different intensities and you need to calculate each separately. And it's hard to come up with an actual training session workload. So you simply calculate the TRIMP for each interval, and then you just sum them together. For example, assume the athlete does a workout of 5 intervals of 5 minutes each, and they do these at 95% of their maximum heart rate. And the athlete recovers by easy jogging for 3 minutes at 70% of their maximum heart rate. So we've got two different training intensities here. So the TRIMP for the run part of the workout is 5 intervals and they were 5 minutes each. And the heart rate zone was 5, and that's equal to 125 units. Plus there were 5 easy jogs in this session, and they were 3 minutes long. They were done in zone 2, and that equals 30 units. Therefore, the TRIMP is equal to 5 intervals times 5 minutes, times the heart rate zone of 5, plus 15 minutes of light jogging in the heart rate zone of 2. And that is equal to (25 x 5) minutes + (15 minutes x 2), and that totals up to be 125 + 30 = 155 units. Okay, so here's another hypothetical example of a week's training schedule for an advanced runner who trains twice a day. So how do you work this in, calculating the training zones for this? The training sessions are different on each day node. So you also want to be able to compare each day. On Monday morning, the athlete does a 30-minute run in a heart rate zone of 2, if you look at the top line there. And the TRIMP for that run is 60. This is the yellow for Monday. And this is fairly straightforward. The TRIMP zone method becomes really valuable, though, when assessing the intensity of the interval sessions as we saw previously. So let's take a look at Tuesday afternoon. On Tuesday afternoon, the athlete does 8 runs at 2 minutes 30 seconds each, and the intensity is in zone 5 for these runs. They also do a recovery between each run at 2 minutes with an intensity in zone 2. So in the athlete's log book, this session is reported as 8 times 2:30 divided by 2 or /2. It's not divided, it's just a /2. So the heart rate zone is 5/2. That is, heart rate zone of 5 during the runs and a heart rate zone of 2 during the recovery. It seems complicated, but it really is quite straightforward, if you just look at these numbers a bit. Okay, so now I'm focused on Thursday. On Thursday afternoon, the athlete's session involved 6 runs, each at 6 minutes each in zone 5 and a 2 minute recovery in zone 2. So you should be able to read these numbers by now. And Friday is a rest day with a very low training load after the hard training load on Thursday. So you can see the total TRIMP scores on that dark blue column there. The easiest way, though, to calculate and plot TRIMP scores across the week is to use a spreadsheet program. Graph A here plots the training load for the morning and afternoon sessions in Graph B plots the total daily training load. So it just combines the morning and the afternoon sessions. Graphing the data in this way provides a visible representation of how the training varies throughout the week. You can easily see that Thursday is a very high training day. Now remember that TRIMP scores are arbitrary units. And for this reason, it is not possible to compare TRIMP scores from one squad of athletes with those of another squad, unless the same TRIMP system is used. However, you can compare TRIMP scores within your own squad and within athletes if you always use the same methodology.