TLT – sounds a lot like a sandwich filling, but it really stands for ‘Threshold-Long-Threshold’, a workout designed as a replacement for your long run that I first read about in a Running Competitor article.
Yesterday was my long run (social commitments meant I moved it from Saturday) and I decided to try out a TLT training session seeing as I had benefited from an extra rest day. In TLT, the basic premise is to do threshold/tempo running at the start and end of your long run, with a session of easy running at ‘long run’ pace in between. If you’re not familiar with threshold running, you can read my earlier post and check out my training page on the subject.
This type of workout has two main benefits. The first is to burn more muscle glycogen early and activate your anaerobic pathway earlier. This will add more fatigue to the long run section and train your body to improve metabolism of body fat for energy, a crucial requirement for successfully going 42km. The second is to train you physically and, more importantly, mentally for the end stages of a race where you need to keep pushing on despite the onset of physical and mental exhaustion.
In the RC article, Magdalena Lewy Boulet of the Bay Area Track Club (coach of Clara Peterson, 16th at the 2012 U.S. Olympic Marathon Trials) says that “threshold ‘cruise intervals’ need to be run at proper intensity. They are meant to be comfortably hard, or about 83 percent of your VO2 max.” This is all a bit technical for us ‘normal runners’ without access to VO2 max equipment, but you can approximate threshold pace to your 5km race pace, or about 85-90% of your max heart rate. If you use a heart rate monitor and are reasonably fit and want to determine your max heart rate, I have used this very instructive Runners World maximum heart rate test to determine my maximum heart rate, and then used the RunnersWeb.com heart rate zone calculator to determine my personal training zones.
The TLT workout in the RC article was a series of 3x2mile threshold repeats done before an 8 mile ‘long run’, followed by another 2 miles of threshold pace. However, this is a workout for someone who came 16th at the Olympic Marathon trials – i.e. not really for mere mortals like us! Therefore, I edited it to reduce the amount of threshold running, and also the total distance, to something I thought would work for me. My workout went like this (MP means Marathon Pace):
- 10 min Dynamic Stretching
- 2km slow jog (MP+45 warm up)
- 3km threshold run at 5k pace (roughly MP-40)
- 17km long run with negative splits (first half MP+30, second half MP+15)
- 2km run to threshold heart rate (equated to MP-10)
- 2km slow jog (cool down)
- 1.5km recovery walk
Unsurprisingly, it was hard! Significantly harder than the long run of the week before which was a straightforward 23km long run with negative splits (first half at MP+30, second half at MP+15). However, I could feel the supposed benefits of a TLT workout happening during the run. After the first threshold section I struggled to slow down to MP+30, showing that my body was still massively creating energy after the initial threshold session, and once I was in the groove of the long run, my body sailed along easily and comfortably. I found that in the second half of the long run the fatigue was greater than usual, and my heart rate gradually crept up towards my threshold level while keeping the pace constant. As it turned out, I had to reduce speed for the 2km before the last threshold element to MP+30 to get my heart rate down into aerobic levels. In that last threshold 2km I really had to push to keep going, both physically and mentally, all good training for the closing stages of a race.
Overall, I consider the session a success, and very ‘instructive’ for reminding me what the closing stages of a marathon are like. However, one ‘negative’ point that I learned with this workout is that I designed it at least 2km too long. The need to slow down for the 2km before the last threshold session told me that I had fatigued too much in the long run component, i.e. I wasn’t fit enough to do the distance with the extra impact of the threshold running. In hindsight, that should have been obvious, but I had countered the extra kilometres with a rest day so thought it would be OK. “Wrong!” – However I still finished the session with all key components completed so overall it was a success.
Would I do this workout again? Yes, I will. It was hard, but rewarding, and I do think the additional physical and mental toughness needed at the end of the workout (when all you would really like to do is walk!) is very good training for race day. I would however do the first threshold session at MP-15 as suggested in the RC article, instead of flat out 5km pace I did.
Would I add it to my normal routine? No, probably not. I think it is a good workout session for those peaking for a marathon, but for generally weekly running it is probably too much to ask to punish yourself like that week-in, week-out if you aren’t preparing for a race. It would just take the fun out of running! It’s also not a particularly useful workout for lower distances either. I think for a half-marathon it could still be applicable, but for 5km and 10km it is the wrong type of training and it would be better to stick to speed work if you are wanting to improve your performance over those distances.
Has anyone else tried TLT training? What was your experience?
Happy running everyone!
Get Going, Get Running!