Endurance 101: Zone 1 - Active Recovery Made Simple

What is Zone 1?

As we have discussed in previous articles in the series the "zone" system refers to a method of attempting to divide the range of an athlete's power output over various durations into a progressive series of numbered zones in ascending order of intensity. This helps to provide a common language both for the description and prescription of training sessions and of intervals. This it does by trying to make these numbered zones as objective as is possible within a complex biological system, grounding them in one or more physiological parameters underlying.

"Zone 1", colloquially known as "active recovery", is the lowest intensity that we can hold while still being described as being in an active - or exercise - state. It's a wide range, delineated at the lower bound only by absolute rest and cessation of movement. Unlike every other zone that we cover, zone 1 is not - typically - used to bring about adaptation via the delivery of a training stimulus. So, what is it good for then?

What does Zone 1 provide, other than stimulation for training?

Very long periods spent in Zone 1 do indeed stimulate peripheral (muscular) adaptations such as increases in mitochondrial content and capillary density, similar to zone2 rides. In fact, for elite-level cyclists, with very high FTPs, endurance rides may comprise a large percentage of time spent at zone 1.

This is because both metabolic burn and muscular tension increase with increased intensities. Although a professional cyclist can easily be metabolically comfortable at zone2, high volume riding at this volume may add stress to the muscles, tendons, ligaments, and joints, which would not be recovered on their own. Similarly, 6 hour endurance ride in zone 2 for professional athlete would go at such a wattage that calories burnt are in no way reasonably be resupplied as would for an amateur athlete to.

On the other hand, however, none of us are international world tour riders with potentially very high aerobic capacities, nor do we normally do ride endurance rides where recovery over a longer time frame for recovery before our next bike workout, so for us zone 1 serves instead two in tandem functions: one at a macro and another at micro scale.

At the macro scale, zone 1 can serve as the intensity for an entire, dedicated active recovery ride.

At the micro scale, shorter periods of active recovery may be performed throughout the course of a longer ride. This second form can be delivered either as unstructured periods such as coasting or soft-pedaling downhill when riding outdoors after a hard hill repeat effort, or structured periods of rest delivered as active recovery intervals in a structured workout, between bouts of work in higher intensity zones, such as zone 5. How does zone 1 feel?

The most significant characteristic of zone 1 intensity is that it doesn't require conscious effort or concentration, even when you're having a full conversation or doing something else. You could almost describe it as "noodling"-it will feel like you're not really exercising at all, just moving.

Zone 1 is roughly the same speed you would use for casual everyday living on your day off when lounging, meandering slowly - window shopping, or walking through a rose garden smelling flowers. It doesn't feel like exercise - if you sweat, it's not recovery pace.

What's the difference between zone 1 and zone 2?

The transition point or boundary between zone 1 to zone 2 is set at a completely arbitrary point since there really is no observable discrete change in state or underlying physiology between the two.

That is, there is nothing specific that occurs within the body as you cross from a Zone 1 to Zone 2. Instead, rely purely on "feel". If it even slightly feels like you have to "work", then you have entered zone 2. What is our body doing in zone 1?

So, if zone 1 training isn't actually delivering very much training stimulus, then what is our body actually doing when we ride in zone 1 at an active recovery pace?

When we pedal, we are using voluntary muscle contraction.

That is, we have to consciously tell our legs to push the pedals. Other parts of our body are, however, under the control of the autonomic nervous system. In fact, it is often said that the autonomic system, together with the hypothalamus and the brain stem, regulates most of the key variables in the body without any conscious input.

These include heart rate, blood pressure, glandular secretion, body temperature, hunger, thirst, plasma volume, and plasma osmolarity. Critically this autonomic nervous system can be on a continuum somewhere between one of two discrete states, both are tonically active, in that they provide some degree of nervous input to a given tissue at all times. These include the sympathetic and parasympathetic systems.

What is a Sympathetic Nervous State?

The sympathetic nervous system readies for extreme physical states that you may hear described as "fight or flight" responses. This readies the body to engage in heavy physical labor, and is substantially increased above resting levels during exercise when the intensity is higher. For example, sympathetic nervous activity may increase our rate of respiration, our rate of heart beat, increase blood pressure, cause adrenals to be dumped into the blood stream, and divert blood away and to specific organs of the body.

In short, our body perceives we are under immediate and probably deadly threat and that it must tweak us for the hypothetical action in order to save us. And the effects of this sometimes can be rather disagreeable, as our body may try to expel our gut whatever way possible.

What is parasympathetic nervous condition?

On the other hand, a parasympathetic nervous state is predominant during quiet, resting conditions and is essentially regenerative in character. The general effect of the parasympathetic system under these conditions is to conserve and store energy, and control basic body functions. It has been called "rest and digest" rather than the "fight or flight" of a sympathetic state.

It is the activation of this parasympathetic state which is achieved via active recovery riding.

What benefits does active recovery have over absolute rest?

As we discussed earlier, our body is normally at some point on a continuum or balance between absolute activation of either the sympathetic or parasympathetic nervous systems. Whilst complete rest is needed at times, such as during sleep, a mildly elevated sympathetic nervous system within a predominantly parasympathetic state (i.e. zone 1) does have its own benefits over total rest.

We gently ride within zone 1. This activates our cardiovascular system only slightly - just enough to increase blood flow, for example.

This increases the supply rate of nutrients, fuel and oxygen to skeletal muscles, e.g. replenishing intra-muscular glycogen reserves. It can also help clear the by-products of exercise (metabolic waste). Both of these activities better prepare those muscles for either further exercise rounds, or increased recovery rate when we do hit a rest state. How should I use recovery pace during a structured workout?

Specific types of workouts that will drive us into a condition of incomplete recovery during the "off" periods to serve a purpose for specific types of adaptation include, such as "over-under" workouts done at threshold. Here, of course, one needs to keep power during the "under" period up to match that which was prescribed during the workout for optimal adaptive signalling.

However, beyond this there are very few times you might want to do a minimum intensity prescription on "off" intervals in HIIT. Workouts are not an exercise in maximizing average power over a ride. Go softer in your recovery intervals using active recovery (zone1), to enable you to go harder in the "on" intervals that follow.

What power or heart rate does active recovery correspond to?

There are guideline numbers both in power and heart rate as percentage of max or threshold, but honestly the best determinant is simply "feel". It is literally impossible to go too easy in zone 1 without falling asleep.

How do I maximize recovery intervals in a workout?

Keep pedaling. Pedal lightly, but still, keep pedaling. Any pedalling at all will allow your body to refuel muscles and clear metabolites from tired muscles and better prepare you for the next working set. Provided your rest interval is two minutes or longer in length, you may also attempt several of the below techniques.

Into the littlest ring at front and back of gear set: littlest of the small, Smally Smalls), while attempting to maintain a reasonable pedaling cadence if you can, but with very slight pedal pressure.

1. Relax the body and shoulders. Stretch.

2. If you have listened to invigorating music at high volume for energy in your workout sets, mute or pause it, or turn the volume right down.

3. Let the blood flow back in to give you that endorphin flow by focusing on your breaths, going through your nose if you can do that, deep breath.

When would be a suitable time for me to plan in a dedicated active recovery ride?

Active recovery rides are best suited for performing immediately after a hard work out or race, and/or on otherwise "off or rest day".

People do active recovery rides pretty wrong-or better said, sub-optimally. I have seen many people on Zwift on B or C pace Robopacers ('bots') at 3w/kg claiming to be "recovering" after having done a race. They aren't, or rather, they aren't doing it optimally.

First of all, stay in zone1, and by feel off the pedals. Choose your very easiest gear. Forget about ERG, forget about training, forget you're on the bike. Just relax and smell the roses.

It may help to hear soothing music - anything will do, soothing classic, soft jazz, chillout - whatever you like. Smell wax lights in the paincave? Sure! Anything works. Just think "spa retreat", not "bike workout".

You may find it helps psychologically not to get fully "kitted" up - taken to extremes just wear casuals, even use flat pedals if you have them. Cap your ride at a maximum of 30-40 minutes, or as soon as you start sweating.

Finally, it can be helpful to drink a recovery shake while on the bike. Your body is shuttling nutrients into your cells, give it the fuel it needs to do so. Unlike at higher intensity, you have full blood flow to your digestive tract when riding in zone1. Avoid high fibre but think easily digestible carbohydrates, vitamins, and a small amount of protein - perhaps "greens powder" in a fruit smoothie.

What else can I use to enhance my recovery?

Active recovery on the bike can be supplemented with passive recovery off the bike - optimizing recovery by making sure we give our body adequate hydration and nutrition that it requires.

Carbohydrates, especially post high-intensity workouts, are vital in rebuilding glycogen stores in our muscles and liver. While fast absorbed sugars and simple carbohydrates work best during exercise, for the rest of the day think complex carbohydrates and more fibre. It's all right to have processed forms like bread and pasta. But best of all are unrefined (unprocessed) forms like wholegrain rice, oats and other cereals, beans, vegetables, fruits- provided you like them- because, on average, they tend to have a better micronutrient profile. We can also try to enhance our parasympathetic state when off the bike by trying to reduce our non-training (life) stress.

This is easier said than done, but stress off the bike will ensure that our sympathetic nervous system is more highly activated. The release of stress hormones such as cortisol can inhibit our recovery, quite aside from being harmful for us in causing hormonal deregulation if chronically elevated. Of course, life can be stressful and finding time and space for this is beneficial even outside the performance of exercise. For you, what works, varies from individual to individual, but you may simply like reading a book, practising yoga, breathing exercises, a soak in the bath, gentle massage - all these things can help.

You may find yourself targeted via advertising on social media for "active recovery" products such as compression trousers, compression socks, ice baths, and percussive massage guns, etc. If you want to try them, then that's up to you-but so far, with a few minor exceptions, there is no research-based evidence supporting their claims on behalf of effectiveness in exercise recovery.

Finally, not "recovery" per se, but the most significant companion to active recovery is simply rest. Sleep specifically is the single most effective means by which one can recover from training or other forms of stress.