Nobody needs a coach to gain fitness. Anyone can tell you to add mileage, do harder intervals or lift heavier. It always works – assuming you have spare time and capacity. It’s also the only way to improve across various event durations. 

Most runners care about their mile time as well as their marathon; most rowers need to maintain a strong 30min test as well as a sprint. For them, more is more, and good training is textbook. As a result, simple tools can predict their performance from a short laboratory test or patterns found in the general population. Rules of thumb become law:

“Do 90min of UT2 every day, then add 10sec to your 2K pace for the erg test!”  …  “Do  long rides to maximise FTP/kg, then race at 78% of that!” … “Build mileage until 3 weeks out and look up your pace from the VDOT tables!”   

But if your performance goal is very specific:

… such as one standardised event or a distance you focus on

… or is limited by muscular endurance as well as fitness

… or there’s only one day in the calendar that matters

then “doing more” could be holding you back.

–  You don’t need a 6:40 2K to pull 1:43 splits for 5K

–  You don’t need a “330-watt FTP” to comfortably push 275w for an IRONMAN

–  You don’t even need to be a quick runner to consistently go sub-3 off the bike.