Hill sprints for distance runners and the speed ceiling

Your aerobic ceiling and your speed ceiling

Three terms from the research are worth knowing:

• Maximal aerobic speed (MAS): the speed linked to your maximal aerobic capacity.
• Maximal sprinting speed (MSS): your top speed, measured in a flying sprint.
• Anaerobic speed reserve (ASR): MSS minus MAS. It is the speed buffer above your aerobic ceiling.

These ideas were set out by Gareth Sandford, Paul Laursen and Martin Buchheit in a 2021 paper in Sports Medicine. They argue that when you work above MAS, the proportion of your reserve you are using is more useful than the percentage of MAS.

Same pace, different cost

Here is an example with illustrative numbers. Two runners both have a MAS of 18 km/h. Both aim to run at 20 km/h.

Runner A is using a third of the reserve above MAS and is working near the ceiling. Runner B is using about a sixth, so the same pace is much cheaper. That is the case for raising MSS: a higher ceiling makes a given pace cost less relative to what you have in reserve, even if your aerobic capacity does not change.

What Athlevo does with it

• Speed ceiling work starts early. Hill sprints begin in Phase 1 and continue through the whole block. Athlevo treats the speed ceiling as slow work that has to start early.
• Profile before programming. Before building a plan, a coach checks whether your limiting factor is your aerobic base, your tolerance for threshold work or your speed ceiling.
• Edge is ceiling work. The Edge zone develops neuromuscular efficiency and adds to MSS over time. It is not race-specific work.

The two Edge sessions

• Surge Hills: short maximal hill sprints. A typical session is 8 to 12 reps of 8 to 10 seconds on a 6 to 10% grade, with a full walk back between reps. Each rep is fully recovered before the next, because this is a speed session, not conditioning. Hills need no track or timing gates.
• Surge Strides: short, relaxed, fast efforts on flat ground, such as 8 × 20 seconds at Edge effort with 90 seconds of easy walking or jogging between. Done with full mechanical relaxation. Fast, never strained.

Edge stays under 5% of weekly volume. It is the sharpener, not the engine. If you are returning from injury or have never sprinted, talk to a coach or doctor before adding maximal efforts.

How a coach measures it

• MAS: estimated from a 1500 to 2000 m time trial at maximal effort.
• MSS: estimated from a flying 20 to 30 m sprint on flat ground or a slight downhill. You accelerate fully before the timed section. A GPS watch with sprint tracking gives a usable estimate.
• ASR: MSS minus MAS, both in km/h.