VDOT Training: Jack Daniels' Pace Tables Explained

Most runners know their race pace but not their training paces. That is exactly where the most common mistake in endurance training is born: easy runs that are too fast and intervals that are too slow. Jack Daniels built one of the most robust answers to this problem — the VDOT value. From a single current race time you derive five training paces, from recovery pace to repetition pace, and each of those zones has a physiological justification. This article explains what sits behind VDOT, how to determine your value, how to transfer the table into your plan, and where the system reaches its limits.

What VDOT is — and what it is not

VDOT is a performance index, not a lab figure. The abbreviation echoes VO₂max, and the dot instead of the small o stands for what Daniels himself stressed: it is a derived equivalent. The idea behind it began with an observation that surprises many runners — the oxygen uptake measured in a laboratory and actual race performance can diverge substantially. Some athletes record a high maximal oxygen uptake in testing and still run mediocre times, because they use a large share of that capacity at race pace. Others measure lower and run faster. The explanation is running economy, plus the ability to hold a high percentage of maximal oxygen uptake over a long period, and that second quality is better trained than inherited.

VDOT therefore works in the opposite direction: instead of estimating a race pace from a lab value, it derives an equivalent from a race performance that actually happened. The output is not just one race pace but five training zones. That is what makes the method usable in everyday training — you need no treadmill protocol, no lactate curve and no performance test, just a race time and a table.

The table itself came from empirical data: Daniels combined race times, oxygen uptake values and metabolic measurements from trained athletes across distances and performance levels. The value is still discussed critically today, because the duration formula he uses to convert a running time into an oxygen uptake does not fit every distance and every racing temperament equally well. The practical benefit is untouched by that debate: anyone who follows the pace targets stays far enough away from the typical load-management mistakes. Background on the physiology of the training zones is in the glossary entry on lactate threshold.

The five intensity zones in Daniels' system

Daniels describes five zones, not three. In each zone the duration of the effort matches its physiological effect — a setup that, inside a training plan, splits into zone 2 training and threshold work. The overview below links each zone to what it triggers in the body and how much of it belongs in a reasonable training week:

• Easy pace (E): The most relaxed zone, roughly 59 to 74 percent of maximal oxygen uptake. It builds aerobic capacity and, above all, structure: mitochondria, capillarisation and the ability to use fat as fuel. The usual mistake is too much speed — the pace must feel easy, otherwise it is no longer E pace. In weekly planning this zone should carry 70 to 80 percent of total volume.
• Marathon pace (M): The pace you can hold for 42.195 km. That places it above threshold pace and clearly below easy pace. The stimulus is mainly specific: running at race pace to train race feel and glycogen economy. Mid-season, a session with M segments builds confidence because the pace is hit repeatedly instead of being guessed on race day.
• Threshold pace (T): Also called comfortably hard — controlled effort in which lactate production and clearance are in balance (steady state). The benefit is anchoring the anaerobic threshold. Runners usually hold this pace for 20 to 40 minutes; rather than one long block, intervals of 3 to 15 minutes are more effective because they keep the pace honest.
• Interval pace (I): VO₂max pace. Intervals run two to five minutes, because that is as long as the pace can be held. The goal is raising maximal oxygen uptake, the engine work that later supports both threshold and race pace. At 3 minutes you are already at 10 percent of total volume at the absolute ceiling.
• Repetition pace (R): The fastest pace on the scale, well above 1500 m race pace. It is used not for cardiovascular stimulus but for running economy, cadence, relaxation and fatigue resistance. Repetitions last 30 to 90 seconds with full recovery in between: strides and running drills are the classic sessions for this zone.

Finding your own VDOT: how to read the table

There are three steps. First, an honest, current race time between 5 km and the half marathon, no more than six weeks old. A training time that was "roughly as fast back then" is no basis; what counts is what happened over a measured course in a race. Second, look the time up in the VDOT table and read the value from the first column. Third, set the coming weeks' zones using the matching pace values.

Which race distance gives the most useful value depends on your goal race. A 5 km result describes a very high speed over a short duration and tends to overestimate performance over longer distances. A 10 km result is the most honest reference for most competitive runners, because it sits close to threshold and fatigue resistance already plays a role. The reference table below shows the five training paces (rounded to 5 seconds per kilometre) for four performance levels, plus the equivalent 10 km time:

The table is orientation, not a replacement for the original tables in Daniels' Running Formula, which go in smaller steps and are accurate to the second. What matters is not the last second anyway but the order of magnitude: between easy and marathon pace there is about a minute per kilometre at VDOT 40, and another 30 seconds down to interval pace. Anyone who knows those gaps can check every target in a plan for plausibility in seconds.

An example week: VDOT 46 in half marathon build-up

How the five zones translate into a real week is best shown by example. Assumptions: a runner with a current VDOT of 46, targeting a half marathon personal best, 55 km weekly volume — not an athlete at the limit of what is possible but one with a solid base. The principle behind the structure is: quality in small doses, volume in the easy zone.

• Monday — rest or 30 min recovery: Very relaxed, well below easy pace (around 6:30 min/km). The day serves circulation, not training.
• Tuesday — intervals, 5 × 3 min at I pace (3:30 min/km): After a 15 minute warm-up and 4 × 20 second strides come the five intervals with 3 minute jog recoveries, then a 10 minute cool-down. Total load of the session: about 10 km.
• Wednesday — easy, 8 km: Pure recovery through volume; the legs absorb Tuesday's tempo work.
• Thursday — threshold, 3 × 8 min at T pace (4:00 min/km): The intervals are deliberately longer than in the I zone but slower. Two minute jog recoveries, the warm-up and cool-down easy. Roughly 12 km in total.
• Friday — rest or 6 km recovery.
• Saturday — easy 6 km plus 6 × 20 seconds at R pace (around 3:10 min/km) at the end, with full recovery between. The short R block trains cadence and economy without leaving fatigue.
• Sunday — long run, 18 km: The last 6 km at M pace (4:20 min/km), the rest easy. Two stimuli in one session without increasing volume.

That is 55 to 57 km with two quality sessions and one specific long run. Time spent above threshold stays under 15 percent of total volume, matching the rule of thumb that recurs throughout the literature on intensity distribution. How the same logic shifts for a polarised or pyramid model is a separate decision — the pace assignment stays the same.

The four most common mistakes in practice

• Easy runs that are too fast: the most frequent mistake of all. Runners who work off E pace often feel they are "not really training" and end up at marathon or threshold pace. The result is a week with three or four moderately hard sessions — the classic grey zone error. E pace according to VDOT feels absurdly slow at first, and that is exactly its function.
• Deriving marathon times from a 5 km result: a 20 minute 5 km produces a calculated marathon equivalent that hardly anyone could run a few days later. For distances from the half marathon upwards you need a time from a comparable duration — running economy and fatigue resistance do not scale linearly.
• Recalculating VDOT constantly: feeling good in one session is not a higher VDOT. Adaptation happens over six to eight weeks. Anyone who checks the table after every easy run pushes their paces up before the base has grown.
• Treating I pace as a training pace: the interval zone is not a tempo pace. Running longer than 5 minutes continuously at I pace no longer targets VO₂max but acute fatigue with high carbohydrate cost. For well-trained athletes it is 3 minutes per repetition with equal to double recovery, and not much more.

Where the system reaches its limits

VDOT is a model, not a measurement. Three weak points are worth knowing. First, extrapolation across distances: converting between 5 km and the marathon loses accuracy when more than one performance factor — endurance, economy, tactics — is affected differently. A very fast 5 km time overestimates the marathon, while a solid marathon time often underestimates short-distance speed. Second, environmental factors: heat, altitude, wind and course profile shift the pace actually possible on a given day; the table describes an ideal world. Third, training history: the equivalents hold for athletes who are broadly prepared across several distances, not for someone returning after a long break.

On top of that comes a principle Daniels himself stresses: VDOT is a planning basis, not a performance diagnosis. The zones say how fast you train in a given stimulus, but nothing about how your fitness develops through a block. That development is read from the load balance — chronic against acute load, plus the form value. How the model calculates internally is in CTL, ATL and TSB, and for the carbohydrate-metabolism side of fatigue the constant comparison with critical speed offers a second angle.

Translating VDOT into the way Peakora works

VDOT is most interesting as a bridge between a race time and a training plan. Once a plan starts from a real performance level, the pace targets fit the person who is supposed to run them, and the legitimate doubts about blanket prescriptions disappear. That is exactly the core of Peakora's engine: pace zones are derived from your current performance level, differentiated by race distance and adjusted as new results come in. The difference from a static table is the feedback loop: when new race times arrive, the zones have to change — the models behind that are described in the marathon training pillar and in the training glossary.

One caveat for context: the tables were built on flat ground in moderate climates, so a runner working from table paces still needs cadence and technique work alongside. Strides and short sprints — the R zone — overlap with work on running technique and running economy; they are the place where speed, cadence and economy are learned together.

Frequently asked questions about VDOT