Britten Hector Haines är elitorienterare och traillöpare, han har flera fina placeringar från VM i orientering och topplaceringar i svenska och internationella traillopp. Den här veckan får vi ta del av ett av Årebaserade Hectors favoritpass "Over and Under intervals". Och det vi ska röra oss över och under, är vår mjölksyratröskel. Vill du veta mer om Hector och hans träning? Den här veckan är det han som har hand om Trailrunning Swedens Instagramkonto @trailrunningswe

Hector presenterar passet:

"Lactate threshold is arguably the most important determinant when it comes to endurance sports. It reflects the maximum intensity and speed that we can perform at between 10 mins and 60-90 minutes effort, before glycogen depletion becomes a factor that creeps in.

Over and Under intervals

The idea with the intervals is that we train and adapt our lactate threshold. It's also great for getting to know your body. It's a session that can simulate that 'race' feeling really well and is great in the pre-season build up.

Reminder on Lactate Threshold: The intensity of exercise your body can 'buffer' or remove lactate acid from your muscles as fast as it is being produced. Over the lactate threshold, lactate acid in muscles builds up (performance of muscles becomes time limited). When we are under the lactate threshold, our muscles can remove the lactate acid and convert it to other metabolites. Going 'over' and 'under' helps with 'lactate shuttle' (using lactate acid as energy).

If you know your heart rate at lactate threshold then great! We aim for 5 bpm above this in the 'Over' interval, and 5-10 bpm under by the end of the 'Under' interval.

HR zones defined by your watch or activity tracker (1-5) should have you working in the top-end of Zone 4 in the 'Over' interval and at the bottom of the same Zone 4 for the 'Under' interval.

If you don't have any measure of HR, you can go by feel. Run the 'Over' intervals at a pace/intensity equal to if you were racing a 8-10 minute race. NB - this is a pretty hard pace. You should feel the lactate acid building gradually in the body after the first minute of the interval. In the under intervals, back off the intensity to around the level you might push yourself in a 45-60 minute race. NB. This will still feel hard, your breathing heavy and your HR high - particularly in that first minute. However, you should feel like everything is coming 'back under control' by the end of the 'Under' interval.

The session is:

Warm up
(3 min 'Over' then 2 minutes 'Under') x3 (15 mins continuous effort)
1 min jog
(2 min 'Over' then 3 minutes 'Under') x2 (10 mins continuous effort)
Warm down

After the session it's important to analyse how it went. What felt easy/good - what was hard? How did your body respond and how fast was it able to deal with the lactic acid? Also analyse how your body feels the evening after, and the day after. Adapt your sleep and recovery appropriately, as well as your training. However, hopefully you'll feel great and ready to push yourself again soon!

Have fun out there!

/Hector