I'm tired but very happy to be the Vuelta race leader

After fighting to take the leader's red jersey at the Vuelta I'm really happy but I'm also very tired.

Obviously I'm very proud of what I've achieved. I missed out on the overall lead on Monday after being in the break but I managed my effort really well on the climb of Sierra Nevada and it paid off.

During the climb I carefully limited my losses, especially when Nibali attacked, because I knew that the climb was hard but that the last part was a little less demanding and at only four or five percent. I knew it suited me better and that I'd have a chance to close a gap or keep things under control. I was extra motivated because I knew I was riding into the red jersey.

I think I'm climbing better than ever. As I explained in an earlier blog, I've done a lot of specific mountain climbing this year and done it at altitude. That's helped me improve my climbing and it has really paid off now.

I've had leader's jerseys at the Tour de France and other stage races but I've usually lost them pretty quickly. Perhaps this time I've taken it at the right time. I hope so. If I lose it, I'll change my strategy and try and win a stage later in the race.

It's going to be hard to keep the jersey because I'm still feeling the huge effort I made when I went in the break on Monday but I'm going to fight all the way to keep it as long as possible. If I can hold on to it during today's up and down fifth stage, then I should be able to hold it for a few more days after that. I've got a 43 second lead on Moreno and more on the other guys. That's not a lot but it's pretty good too.

I'm sure a rider like Joaquim Rodriguez of Katusha will go on the attack on the steep climb to the finish. It's perfect for him. I've heard it's got a gradient of 23% at one point. Fortunately it's only for one kilometre and so it might not make big gaps and splits in the peloton.

The heat here in Spain has been terrible. The temperatures have been close to 40°C and so the amount of liquids you need to take on board is enormous. We have to drink a lot of bottles but that means you are full of water and when you finish the stage, you feel very bloated. It feels like you're about to explode.

You have to try and stay cool by pouring water over yourself. I don’t usually like doing that but here there's no choice. Just like a car, we've got to keep our engines cool too.

Wish me luck for during the stage and hasta luego –hopefully still in the red jersey.