Since January I've been running approximately 25 miles a week, a little more the last few weeks. I'm 37, male, 6' and 165lbs. I cannot keep a zone 2 heart rate at even the slowest of shuffles despite the mileage, but I can nose breathe through an 8 mile run at my slowest pace, which, again, is a shuffle, not a full stride. HR is always in the 150s and 160s. I cannot nose breathe at all with a full stride and HR jumps into the 170s.
Am I supposed to keep going with the really short-strided shuffle for now because it allows me to nose breathe through entire runs? My pace is usually between 12:30 and 13:00 a mile on these runs, and they basically don't seem to be getting any faster or easier. My watch is also telling me I have too much vertical oscillation, and I can feel it, like I'm slamming into the ground with each step - is this likely because of the short-strided shuffle I have to do to keep the effort low?
I just really thought that after four months I'd have more progress to show for all this. Is it time to get a coach to take a look at my stride, or just keep with it at a pace where I can keep nose breathing?