What I like about LTP (or Threshold) runs
LTP runs are training runs at "Threshold pace" which is on the line between where your muscles can work aerobically and anaerobically ; as a rule it is roughly the pace you can run fast for an hour or so. Probably close to 10k pace or thereabouts anyway. See here for a more informed discussion . What they are for? My marathon plan contains a few of these, and they are daunting at first. They build from 3 miles in the early weeks, through timed ones (e.g. 16 mins / 4 mins recovery / 14 minutes - where distance depends on speed). The goal is to help build the body's ability to run "on the limit" and deal with lactic acid build up in muscles, effectively training the body to get better at that particular biological process. They also (IMHO) give you a decent benchmark of how fit, fast and well trained you are - and to an extent - how well mentally you can deal with the pain of running hard. Certainly they are a long, long way from a chatty or long/slow...