Every training plan is built from a handful of named runs and workouts, each with a job to do. This hub explains them in plain English -- the easy aerobic runs that build your base, the faster sessions that build speed, the physiology behind training zones, and how to pace and structure it all around a race.

Easy & steady runs

Easy Run

What is an easy run?

An easy run is a run done at a comfortable, relaxed pace where breathing stays controlled and you could talk in full sentences. It is the everyday workhorse of training, where the goal is time on feet rather than speed. Most runners do the majority of their weekly mileage at this effort.

Why it matters

Easy running builds the aerobic base that everything else is built on. It strengthens the heart, grows the network of small blood vessels in the muscles and teaches the body to burn fuel efficiently, all without the heavy fatigue of hard sessions. Done consistently, it lets you train more often and recover faster.

How it is paced

The simplest guide is the talk test: if you cannot hold a conversation, you are going too fast. By heart rate it usually sits in the lower zones, well below threshold. New runners are often surprised at how slow easy should feel, and slowing down is one of the most common improvements coaches suggest.

What to look for

Aim to finish an easy run feeling like you could have carried on. If you feel wiped out, the pace was too high. Keeping easy days truly easy is what makes hard days effective, a balance often called polarised training.

Recovery Run

What is a recovery run?

A recovery run is a deliberately slow, short run done when the body is tired, usually the day after a hard workout or a long run. It is even gentler than an easy run. The purpose is not fitness gain on the day but to keep the legs moving and help them recover.

Why it matters

Light movement can encourage blood flow to fatigued muscles, which some runners feel helps loosen stiffness and speed recovery. Just as importantly, it adds easy aerobic time without the strain of a normal session, helping build volume safely across a week.

How it is run

A recovery run is paced by feel: very relaxed, with no pressure on time or distance. It is typically 20 to 40 minutes and noticeably slower than your easy pace. If you feel worse as it goes on, it is fine to cut it short or walk.

What to look for

You should finish a recovery run feeling looser and no more tired than when you started. If a session leaves you drained, it was too hard to count as recovery. Some runners prefer full rest instead, and both approaches are valid.

Long Run

What is a long run?

A long run is the single longest run in your weekly schedule, usually done at a comfortable, easy pace. It gradually extends the distance or time you can cover. For distance runners it is often the most important session of the week.

Why it matters

The long run builds endurance by training the heart, muscles and energy systems to keep working over a sustained period. It improves how efficiently the body uses fat for fuel, strengthens the legs for the demands of racing, and builds the mental resilience of staying out longer.

How it is structured

Most long runs are run easy, by time or distance, and lengthened slowly week to week to avoid overload. More advanced plans sometimes add faster finishes or marathon-pace segments, but the classic version is simply a steady, relaxed effort that you can sustain throughout.

What to look for

Build long-run distance gradually and keep the pace honest so you can recover for the rest of the week. Fuelling and drinking become important as the run gets longer. The aim is to finish tired but in control, not completely emptied.

Aerobic Base

What is an aerobic base?

An aerobic base is the underlying endurance fitness that comes from running regularly at easy, aerobic efforts over a long period. It reflects how well your heart, blood vessels and muscles deliver and use oxygen. It is the foundation that the rest of your training is built upon.

Why it matters

A bigger aerobic base means you can handle more training, recover quicker between hard sessions and sustain effort for longer. Without it, faster work has shaky foundations and injury risk rises. Most endurance success rests on patiently developing this base first.

How it is built

The aerobic base grows through consistent, mostly easy mileage accumulated over weeks and months. Volume and frequency matter more than intensity here. This is why many plans start with a base phase of steady running before introducing harder sessions.

What to look for

Signs of a strong base include feeling comfortable at easy paces, recovering quickly and being able to add training without breaking down. It is built slowly and lost slowly, so consistency over time is the key, not any single big week.

Zone 2 Running

What is zone 2 running?

Zone 2 running refers to running at a heart rate in the second of five common training zones, a low and comfortable intensity. In practice it lines up closely with easy, conversational running. It is the zone most endurance plans spend the majority of their time in.

Why it matters

Training in zone 2 develops the aerobic system efficiently: it improves the body's ability to burn fat for fuel, strengthens the heart and grows the small blood vessels in the muscles. Because it is low stress, you can do a lot of it without heavy fatigue, building fitness sustainably.

How it is defined

Zone 2 is usually set as a percentage band of maximum heart rate or based on a measured threshold. The exact numbers vary between methods and individuals. A simple guide is that zone 2 should feel easy and conversational, matching the talk test for easy running.

What to look for

Many runners find their easy pace sits above true zone 2 and need to slow down to stay in it, especially on hills. Using heart rate keeps the effort honest. The aim is patient, comfortable running that builds aerobic fitness without strain.

Faster sessions

Tempo Run

What is a tempo run?

A tempo run is a continuous effort held at a comfortably hard pace, where breathing is heavy but controlled and talking is limited to short phrases. It is sometimes called the fastest pace you could sustain for around an hour. The effort is steady rather than flat out.

Why it matters

Tempo running trains the body to run faster before fatigue builds up, by improving how it handles the by-products of hard effort. Over time this lifts the pace you can hold for sustained periods, which directly helps races from 5k up to the marathon.

How it is structured

A typical tempo session is a 20 to 40 minute sustained effort, or several long blocks with short recoveries, all wrapped in an easy warm-up and cool-down. The key is holding an even, controlled pace rather than starting too fast and fading.

What to look for

The effort should feel hard but repeatable, never a sprint. If you are gasping or slowing badly, you started too fast. A good tempo finishes strong and even, showing you judged the pace well.

Threshold Run

What is a threshold run?

A threshold run is a sustained effort held right around your lactate threshold, the intensity where the body shifts from comfortably clearing fatigue by-products to letting them accumulate. The pace is firm and focused, harder than easy running but still controlled.

Why it matters

Threshold training pushes the point at which fatigue starts to win. By repeatedly running at this edge, the body gets better at clearing lactate and sustaining quicker paces. It is one of the most effective sessions for improving race times across distances.

How it is structured

Threshold work can be one continuous block, similar to a tempo run, or broken into longer repeats such as several blocks of five to ten minutes with short recoveries. Keeping the effort precise matters, because going too hard turns it into a different, more draining session.

What to look for

The effort should sit on the edge of comfortable, sustainable but demanding. You should be able to repeat the pace across the whole session without falling apart. If you are forced to slow dramatically, you were above threshold, not at it.

Interval Training

What is interval training?

Interval training is a structured workout that alternates bursts of hard running with periods of easy jogging or rest. By breaking fast running into chunks, you can spend far more time at high intensity than you could in one continuous effort. It is the classic way to build speed.

Why it matters

Hard intervals push the heart, lungs and muscles to work near their limits, which develops the high-end fitness that easy running cannot reach. The repeated efforts also sharpen running economy and leg turnover, helping you feel faster and smoother at all paces.

How it is structured

A session is defined by the length of the effort, the pace, the number of repeats and the recovery between them. Examples range from short, fast repeats with full recovery to longer, controlled repeats with brief jogs. The recovery is deliberate, allowing enough freshness to hit the next effort.

What to look for

The goal is to complete the set at an even, repeatable quality, not to blow up on the first rep. If the last efforts are much slower, you started too hard. Good intervals leave you tired but having hit the target paces throughout.

Fartlek Training

What is fartlek?

Fartlek is a training run that blends faster surges into easy running without a rigid structure. The word is Swedish for speed play, and that is the spirit of it: you pick up the pace for a stretch, then ease back to recover, repeating as you like. Efforts can be marked by landmarks, time or simply how you feel.

Why it matters

Fartlek delivers many of the benefits of interval training, such as faster paces and varied effort, but in a relaxed, adaptable form. It is great for breaking up routine, learning to change gears, and getting a quality session in without a track or strict plan.

How it is structured

A fartlek can be as loose or as planned as you want. A classic version is surging to the next lamppost or tree, then jogging to the one after. A more structured version uses set times, such as one minute hard then two minutes easy, repeated through the run.

What to look for

The strength of fartlek is its freedom, so use it to play with pace and listen to your body. Keep the easy parts genuinely easy so the surges have quality. It suits runners who find formal intervals dull or who train on varied terrain.

Progression Run

What is a progression run?

A progression run is a continuous run that starts comfortably easy and gradually increases in pace, ending at a firm, controlled effort. There are no recovery breaks; the speed simply builds across the run. The final stretch is the fastest part.

Why it matters

Progression runs train the body to run quicker as fatigue sets in, which mirrors the demands of racing. They also build discipline and pace judgement, because starting too fast makes a clean progression impossible. The result is a single session that blends endurance and speed.

How it is structured

A common approach splits the run into thirds: easy, then moderate, then strong. Others build pace more gradually across the whole distance. The exact paces matter less than the steady upward trend and a controlled, strong finish rather than an all-out sprint.

What to look for

The key is restraint early on so you have something left to speed up with. A well-run progression feels controlled throughout and strongest at the end. If you fade instead of building, the early pace was too quick.

Hill Repeats

What are hill repeats?

Hill repeats are a workout where you run hard up a hill, jog or walk back down to recover, and repeat for a set number of efforts. The climb adds resistance, so the muscles work harder than on the flat, while the slower speed keeps impact lower.

Why it matters

Running uphill builds strength and power in the legs and hips, sharpens running form, and develops fitness in a way that is gentler on the body than flat-out sprinting. Many coaches use hills to build a strength base before moving to faster track work.

How it is structured

Sessions vary by hill length and gradient. Short, steep repeats of 30 to 60 seconds build power and speed, while longer hills of two to three minutes build strength endurance. The downhill jog is the recovery, and form on the descent should stay relaxed and controlled.

What to look for

Focus on strong, driving form rather than just survival: tall posture, active arms and a powerful push. Keep the efforts even across the set. The hill naturally controls impact, which is why hills suit runners building strength or returning from a niggle.

Track Session

What is a track session?

A track session is a workout run on a standard 400 metre athletics track, usually made up of repeats at a set distance and pace with recovery between them. The track's measured, even surface lets you control distance and pace far more precisely than on the road.

Why it matters

Precision is the main benefit. Knowing each lap is exactly 400 metres makes it easy to judge pace, compare efforts and track progress over time. The flat, predictable surface also removes the variables of hills and traffic, so you can focus purely on the effort.

How it is structured

Sessions are built from repeats such as 400s, 800s or 1000s at a target pace, with jog recoveries. A warm-up and cool-down bookend the work. The standard track means a session can be described simply, like six times 800 metres, and repeated or progressed week to week.

What to look for

Run in the inner lanes for accurate distances, and aim for even splits across the repeats. The track rewards consistency, so the goal is hitting the same pace each time rather than racing the first rep. It suits runners who like structure and measurable progress.

Physiology & zones

VO2 Max

What is VO2 max?

VO2 max is the highest rate at which your body can take in, transport and use oxygen during intense exercise. It is usually expressed relative to body weight. Think of it as the size of your aerobic engine: a higher VO2 max means more oxygen available to power hard running.

Why it matters

VO2 max sets an upper limit on how much aerobic work you can do, so it is a strong marker of endurance potential. While it is not the only factor in performance, raising it lifts the ceiling that other qualities, like efficiency and threshold, work beneath.

How it is developed

VO2 max responds best to running at or near the effort that demands maximum oxygen uptake, typically hard intervals of around three to five minutes with recovery. Easy running supports it by building the aerobic base, but the sharpest gains come from these demanding sessions.

What to look for

Fitness watches estimate VO2 max from heart rate and pace, which is useful for tracking trends rather than exact numbers. The most meaningful sign of progress is being able to hold harder efforts for longer. It improves most in newer runners and plateaus as fitness matures.

Lactate Threshold

What is lactate threshold?

Lactate threshold is the intensity at which lactate, a by-product of hard effort, starts to build up in the blood faster than the body can remove it. Below this point effort feels sustainable; above it, fatigue accelerates. It roughly marks the fastest pace you can hold for a long time.

Why it matters

For endurance running, lactate threshold is one of the best predictors of performance. The higher the pace you can run before crossing it, the faster you can race over distance. Much of structured training aims to push this threshold to a quicker pace.

How it is developed

Threshold improves through sustained running at or just around that intensity, such as tempo and threshold runs. This teaches the body to produce less lactate at a given pace and to clear it more effectively, moving the threshold to a faster speed over time.

What to look for

Threshold effort feels comfortably hard: controlled, with heavy but steady breathing. It can be estimated from race results or heart rate, though lab testing is the precise method. Tracking whether your threshold pace is getting quicker is a clear sign of progress.

Anaerobic Threshold

What is anaerobic threshold?

Anaerobic threshold is the effort level at which the body shifts toward producing energy without enough oxygen, so fatigue by-products accumulate rapidly. It sits close to the lactate threshold, and in everyday running the two terms are often used to mean the same thing: the edge of sustainable hard effort.

Why it matters

Above the anaerobic threshold, you can only keep going for a limited time before slowing. Knowing roughly where this point sits helps you pace races and judge how hard a session really is. Pushing the threshold higher means you can run faster before tipping into unsustainable territory.

How it is developed

Like lactate threshold, it responds to sustained running at a comfortably hard effort and to controlled threshold intervals. These sessions train the body to delay the rapid build-up of fatigue, effectively raising the speed at which the threshold occurs.

What to look for

You can feel the anaerobic threshold as the moment breathing becomes laboured and the effort no longer feels repeatable for long. Heart rate monitors and race performances give rough estimates. The clearest sign of progress is holding faster paces before that laboured feeling arrives.

Pacing & race structure

Race Pace

What is race pace?

Race pace is the pace you intend to run for a particular race distance, for example your goal marathon pace or 5k pace. It is specific to the event and your target time. Sessions at race pace rehearse exactly the effort you plan to sustain on the day.

Why it matters

Practising race pace makes it feel familiar and controlled, so you are less likely to start too fast or misjudge effort. It also conditions the body to run economically at that speed. The shorter the race, the faster the pace; the longer the race, the more sustainable it must be.

How it is trained

Race-pace work appears as segments within longer runs or as dedicated repeats, such as blocks of marathon pace inside a long run, or 5k-pace repeats on the track. The aim is to accumulate time at the target effort while staying relaxed and even.

What to look for

Good race-pace running feels smooth and repeatable, not strained. If your goal pace feels impossible in training, the target may need adjusting. Nailing even, controlled race pace is one of the best ways to build confidence before an event.

Negative Split

What is a negative split?

A negative split is when you cover the second half of a race or run faster than the first half. So a marathon run in two halves of equal time would be even; if the second half is quicker, it is a negative split. It is the opposite of starting fast and slowing down.

Why it matters

Negative splitting is often the most efficient way to race because it avoids the heavy fatigue that comes from going out too hard. By holding back early, you conserve energy and finish strong, frequently with a faster overall time and a better experience than fading badly.

How it is done

The key is discipline in the opening miles, running slightly slower than feels natural while fresh. As the race goes on and others tire, you gradually lift the pace. It takes practice and a good sense of your sustainable effort to judge correctly.

What to look for

A well-executed negative split feels controlled early and strong late, passing runners in the closing stages. The hardest part is restraint at the start, when adrenaline pushes you to go faster. Practising it in training builds the patience it requires.

Positive Split

What is a positive split?

A positive split is when the second half of a race or run is slower than the first. It is the opposite of a negative split and the most common way runners actually finish, often because they set off faster than they could sustain.

Why it matters

A small positive split can be fine, but a large one usually signals a pacing error: too quick early, then a painful fade. Understanding positive splits helps you spot this pattern and learn to start more conservatively, which often leads to faster overall times.

How it happens

Positive splits typically come from adrenaline and fresh legs at the start, leading to a pace that cannot be held. As fatigue and depleted fuel take over in the later stages, the pace drops. The bigger the early overreach, the worse the late slowdown.

What to look for

Reviewing your splits after a race shows whether you faded and by how much. A heavy positive split is a clear cue to practise pacing and restraint. The aim for most runners is to flatten that fade toward even or negative splits.

Taper

What is a taper?

A taper is the deliberate easing of training in the lead-up to an important race. Volume is cut back while some intensity is usually kept, so the body can recover from the hard weeks of training without losing the fitness already built. It is the bridge between training and racing.

Why it matters

Heavy training carries fatigue that masks your true fitness. A taper lets that fatigue clear so the fitness underneath can show on race day. Tapering well often makes the difference between a flat performance and a sharp one, even though no new fitness is gained.

How it is structured

Taper length depends on the race: a few days for a 5k, one to three weeks for a marathon. The common approach is to reduce total volume noticeably while keeping a little intensity to stay sharp. The longer and harder the buildup, the more taper is usually needed.

What to look for

During a taper it is normal to feel restless or even sluggish before freshness arrives, a feeling sometimes called taper madness. Trust that the work is done. The goal is to reach the start line rested, not to cram in last-minute training.

Running Volume

What is running volume?

Running volume is the total quantity of running you do, most often expressed as weekly mileage or total time on feet. It captures the overall training load from all your runs combined, rather than the speed of any single session.

Why it matters

For endurance, volume is one of the strongest influences on fitness. More consistent running, within what your body can absorb, builds a bigger aerobic base, stronger legs and better efficiency. Many improvements come simply from sustainably running more over time.

How it is managed

Volume is built gradually, since the body needs time to adapt to extra load. A common guideline is to increase weekly volume modestly and to include easier weeks so the body can recover and absorb the work. Most volume should be easy running, with only a small share at hard efforts.

What to look for

The right volume is the most you can handle while staying healthy and recovering well, which varies hugely between runners. Warning signs of too much include nagging fatigue, niggles and poor sleep. Consistency at a sustainable volume beats big weeks followed by breakdowns.