Craig, Im a fitness professional and have questions like this asked all the time and there lots of studies to back it up... personally i have run 5 marathons all of which my ave Heart rate has been somewhere between 165 - 175...(im 32) I wouldn't worry too much as long as you feel comfortable (ish) and that you could hold a conversation... It will improve but your resting heart rate is pretty good.. Dont get too bogged down with the science - just make sure you fuel your body with the correct food and water as if you were an olympic athlete and it will make a big difference
Hey there Soph With my professional head on I would say the general rule is if its all in your head its ok to train If its on your chest and you have a temperature dont! Ive had a cold for the last three days and the last thing I feel like doing is running but im getting itchy feet sitting here watching everyone else train..
The week before is also when im most tired - although it never stops me running! I run really well the first couple of days of my period and mentally it helps to know your beating the water retention
I thought i was going to have a nightmare with my 3 hour runs and the need for a shall we say 'comfort stop' but exercise seems to slow the flow - sorry just being honest