Coaching Principles

Speed Sessions and Specificity

Why fast is not the point, and what your training is actually meant to rehearse.

Speed work is one of the most misread parts of a trail and ultra program. The word itself sends most of us straight to a track, to pace targets, to the idea that the session is only working if the watch says something impressive. The principle underneath it is quieter, and more useful.

What speed work is really for, how specificity decides whether any of it transfers to race day, and how both shift across your cycle and across a training block. That is the ground this covers.

First, redefine the word

What we actually mean by speed

In trail and ultra, the honest truth is that raw speed barely features. Your race pace can sit 20 to 40 per cent slower than your training pace, and a good portion of any long climb is power hiking, not running. So a quality session is never about being fast for its own sake. It is about applying a specific stress with enough precision that your body adapts to it.

That reframe matters, because it changes what a session is allowed to feel like. The goal is not a number. The goal is time spent at the intensity that drives the adaptation you are chasing, whether that is a higher ceiling, a higher threshold, or the durability to hold form when you are tired.

The sessions that earn their place

Three kinds of quality, one easy base

Most runners only need three quality categories sitting on top of a deep easy base. Each one targets a different physiology, and each is defined by how long you hold the effort and how much you rest, not by a pace on a screen.

2 non negotiables sit underneath all of it. Any session longer than 60 minutes at intensity needs carbohydrate while you run it, and you leave at least 48 hours between any two hard days. Within session, women hold up well to fatigue, but that does not shorten how long you need to recover between sessions.

The principle that ties it together

Specificity: train the race you are actually running

This is the principle that decides whether your quality work transfers at all. Your race has a shape: its terrain, its vertical, its duration, the fact that you will be eating and drinking the whole way, and the fact that the hardest kilometres come when you are already tired. Good training rehearses that shape rather than ignoring it.

In practice that means a few things. Most of your hard intervals belong uphill, because you spend far more of a race climbing than descending, and a one per cent gain in climbing economy returns more total time than anything you can do on the flat. It means your long runs grow into race rehearsals, with deliberate steady efforts late in a build so you practise holding form on fatigued legs. And it means treating fuelling and terrain as trainable skills, not race day surprises.

The piece runners most often miss is durability. A modest ceiling paired with excellent durability will beat a high ceiling with poor durability in any race over about four hours. Ultras are run by tired athletes, not rested ones, so the most specific thing you can train is the ability to keep performing as the fatigue piles up.

How to anchor intensity

Effort is the currency, not pace

If specificity is the principle, perceived effort is the tool that makes it work. On technical terrain or in heat your pace can swing 3 to 4 minutes per kilometre for the exact same physiological effort, so a pace target on a climb is close to meaningless. Effort, rated honestly, travels with you across every surface and every condition.

It also travels across your physiology. Heat, a poor night of sleep, a heavy week at work and your cycle phase can all lift your effort at the same output. When that happens you adjust the pace or the volume, not the effort target. The session is still doing its job. Your RPE is information, not a complaint.

The female lens

Speed and specificity across your cycle

This part is too often left out. Your hormonal phase changes how speed work feels and how well it lands. In the follicular phase, rising oestrogen brings a lower core temperature, faster recovery between reps and a higher tolerance for hard efforts, which makes it the natural home for your sharpest VO2max and threshold work.

In the luteal phase, effort sits 1 to 2 points higher at the same output, your heart rate runs a touch faster and the heat cost is greater. The move is not to abandon quality, it is to adjust it. Drop a rep or two, add 30 to 60 seconds of rest, or swap a VO2max session for steady state. Same feel, not the same numbers. If you are on hormonal contraception, lean on effort rather than heart rate entirely, since the numbers no longer map cleanly.

There is an upside worth naming too. Running your hard intervals uphill is not only more specific, it is also protective. Slower uphill speed means lower impact forces, which matters because women carry a higher bone stress and tibial loading risk than men under the same training. And when it comes to the long stuff, women tend to hold a higher proportion of their starting force across long efforts and pace more evenly, an advantage that grows the longer the race goes.

Putting it on a calendar

How it sharpens toward race day

Specificity is not a fixed setting, it increases as you move through a build. Early on, the work is broad and general: easy volume, the long run, and an introduction to steady state. Threshold blocks come in through the middle weeks, and VO2max blocks sit later, kept short at around 10 days to two weeks because the ceiling sharpens quickly and costs a lot to hold.

As the race nears, the training starts to look more like the race itself. VO2max is tapered out first because it is the least specific to a long day, while threshold and steady state are maintained, and the long run carries deliberate race effort segments. By the taper you are down to one hard session a week with volume pulled back, holding sharpness without adding fatigue. The closer you get, the more your week should resemble the day you are training for.