What are the physiological work demands in gravel racing and how are these demands best met in training in order to optimize performance in races.
The best way to find out how to train for racing, is to look at the physiological works demands. More specifically - what is required from the different energy system to race fast?
In a recent post ' A quick dine into power data from Danish gravel nationals' ' we looked at race data from the Danish gravel nationals, just to get an idea of what energy systems that are taxed the most during gravel racing.
Five things were quite clear from the race analysis - and analysis of data from many other gravel races.
Gravel racing stresses all energy systems. Thus you need to train all energy systems well.
A relative high percentage of total race time is spent in power zones 5 and 6. A clear indication that the ability to put in high intensity efforts taxing VO2max and the anaerobic capacity, is of major importance and decisive for race performance.
Anaerobic threshold (zone 4 riding) also plays a big part in gravel race performance, as you need the ability to sustain relatively high power outputs over longer periods of time. So a 'high' anaerobic threshold will make the body more resilient to these efforts.
A strong endurance base (primarily zone 2 work) is needed to compete in gravel races, as it will make the body more 'fueling efficient' i.e metabolic flexible. This is the ability to use both carbohydrates and fat as fuel, and adapt the to changes in energy demands. So when intensity gets high the body is good at using carbohydrates and when intensity gets low to moderate the body will be good at using fat as fueling. Thus better sparing of the limited stores of carbohydrates.
The ability to produce high force-low cadence efforts is needed, when accelerating from low speed or overcoming 'tough terrain and demanding surfaces' (steep climbs, loose gravel, mud, sand and the like).
Nature also plays a big part in deciding the demands in gravel racing. It's not just like riding on the road. Asphalt is more or less asphalt, but gravel is not just gravel!
Work demands is at some point determined by the terrain and surface, which will often change during a race. Further weather conditions can have a major impact on riding conditions. You can't do much about the weather, but there are a few things you can consider and plan into you training to meet the overall demands from terrain and surface.
The primary surface in gravel racing is gravel, and as gravel is rough and loose compared to asphalt, the rolling resistance is higher. This makes it harder to coast along at low intensities, and when sitting in a group you need to put in more watts to keep a certain speed compared to the road. So even just riding in zone 2 on a gravel road requires more energy, compared to road cycling.
The secondary surface are trails and the like. Often these can be either with 'grass and roots' or 'stones and rocks' or a combination of the two. Overcoming trails will require bike handling skills and power to conquer obstacles along the way.
Loose, sandy or muddy surfaces are also expected on gravel race courses. Conditions that makes the bike sink or slide and the back wheel spin (specially on steep climbs), makes the need for 'big gear grinding' and 'powering through' at often low cadences essential.
The overall variety in terrain from flat gravel roads to shorter steep climbs, longer moderate climbs and high speed or technical descents, makes gravel racing very demanding physically and technically.
One more thing to consider is that overall energy demands on the body often is higher compared to riding on the road. Due to the terrain and surface the stabilizing muscles will work harder, and this muscle activity is an add on to the energy requirements normally seen in road cycling.
So, how to train for gravel racing:
You need a solid endurance base to be metabolic flexible in order to preserve carbs for decisive high intensity efforts. So lots of zone 2 work is a must!
High intensity interval training is key to prepare for the decisive moments in gravel racing. Specially your VO2max and ability to push the pedals in zone 5. Further some anaerobic effort is also needed for short steep climbs or attacks.
A well trained anaerobic threshold will serve you well, as you will be better prepared to push hard for longer periods of time, and more resilient to difficult terrain and surfaces.
Functional on-bike strength is crucial for periods requiring high force-low cadence in tough terrain and demanding surfaces.
Training your gut and the ability to take in sufficient amounts of carbohydrates during racing, will secure better energy levels during a race, and leave you with more carbs at the latter part of the race.