I do my runs on Mondays, Wednesdays and Fridays, and for some reason, Wednesdays have always been the toughest. Perhaps the 2-hour dog agility training session and the 2 and a half hour round trip to the training venue and back the night before has something to do with it. On Tuesdays, I rarely get to bed before midnight, and often wake up tired and "flat" the next day - not an ideal start when you're planning a mid-morning run. I've just completed week 6 run 2, but boy did it take some willpower! Thank goodness for doggy pulling power, that's all I can say!
I think week 6 may need repeating, just like week 2 did. Having just read several comments about how tough week 7 is, a rerun (no pun intended) of week 6 may be wise. I don't mind, with my dodgy knees I'd rather be safe than sorry. I'm not a great fan of "no pain, no gain" theory - for me, pain is soon followed by complete failure, so I'd rather gain slowly without pain, thank you very much. I'm frankly amazed I've made it this far.
One question: how many of you stretch properly after after your runs? I decided right from the start that I would finish every run with some good, long leg stretches, as well as a couple of back stretches. I became aware of the need to stretch when I joined a yoga class a couple of years ago. My class mates consisted largely of keen runners, cyclists and riders, ranging in age from 18 to mid-50s. Looking at these fit specimens, I thought I would be right at the bottom of the class and struggling. But no, it soon became clear that although dedicated runners, cyclists and horse-riders may look fit enough, their joints, tendons and ligaments are often seriously creaky. So when I started C25K, I made myself promise to keep working on my flexibility as well.
I also find that my yoga exploits have really helped me improve my running technique. It has made me very aware of my breathing and has helped me control it right from day 1. Since much of the stretching of yoga relies on the practitioner learning to tighten and relax his or her muscles at will to achieve the various poses, I also found that this awareness of what my muscles are doing has helped me work on my running technique. In the first couple of weeks, I was prone to tighten up my neck and shoulders but once I became aware I was doing it, running became much more comfortable. My left knee is particularly bad, and the muscles in that leg have had years to get used to switching on automatically to protect the joint, with the hamstring being particularly affected. But the awareness that yoga has brought allows me to relax the muscles in my legs and the tension in the left hamstring even during runs, which lets me stride out much more freely and overcome excessive tiredness as the runs have got longer.
I suppose that as with most things in life, balance is the key - by all means build strength and endurance, but stay flexible as well.