Most of the running community – coaches such as myself, magazines, and runners – focus mostly on race specific training or recovery periods. But what happens in the times of year between racing and recovering? The base phase is what happens – and here’s why the base phase matters for runners.
The base phase occupies the training between recovery weeks and race specific training. If you are racing (not just running) a spring half marathon and a fall full marathon as your goal races, then the early winter and summer months will be your base phase.
What is Base Phase Training?
The base phase is a period of training focused on building your foundation of aerobic fitness. By building this foundation before you begin race specific training, you are able to move to the next level in mileage, pace, or intensity in race specific training and improve by a greater percentage in your next goal race.
Since the base of all distance running, whether you prefer the 5K or marathon, is aerobic endurance, the base phase emphasizes a high volume of easy aerobic running. Short interval or threshold workouts are included for strength and speed development during this period.
If you neglect strength training, the base phase is the ideal time to incorporate it. Since you don’t have to worry about being sore before your next long tempo run or mile repeats, you can spend 2-3 days per week strength training for 30-40 minutes.
The Base Phrase Reduces Injury and Plateaus
Hard workouts such as long tempo runs and VO2max interval workouts are effective because they place a large amount of stress on your body. Your body responds to that stress by strengthening certain physiological systems – better oxygen uptake and delivery, faster recovery, more velocity, improved running economy, etc.
Peak training periods place a large amount of stress on your body with two hard workouts per week plus a long run. Think of how fatigued you feel during the peak week of marathon or half marathon training. These periods are called peak training periods for a reason – you are attempting to create a high level of fitness to run a PR or beat the completion in your age group.
But you can’t sustain that high of a volume of hard training for much longer than the 10-16 weeks leading up to a race. Without a period of lighter training, steadily increasing your training will lead to a plateau after a few months – or worse, an overuse injury.
Base Training Phase Improves Fitness
Research, such as this study in Frontiers in Physiology, indicates that the most effective base building program involves a majority of easy running (approximately 84-95%) with short yet deliberate faster running such as short tempos, steady state runs, and fartleks. When the race specific begins, the threshold and interval training increases.
As Matt Fitzgerald argues in his book 80/20 Running, the balance of a majority of easy runs with a small percentage of hard running is the most effective and sustainable method for becoming a faster runner. You minimize training fatigue while maximizing your aerobic gains with this ratio of easy to hard running.
One of the goals of the base phase is to increase and then maintain slightly higher mileage – so 35-40 miles per week if you were previously at 25-30 miles per week, etc. Increasing both weekly mileage and intensity at the same time can lead to injury or overtraining, so it’s optimal to build mileage during the base phase instead of during the peak weeks of race training.
It sounds counter-intuitive to think that doing less hard workouts will make you faster over time, but the it’s true! The base phase lays the foundation for higher aerobic fitness, which in turns means you can train at a higher level for any given race distance after the base phase.
Base Phase Workouts
The notion of 85-95% of your mileage at an easy pace should guide your base phase training plan. For those who run 3-4 times per week, this means one hard workout per week. If you run 5-6 times per week, your volume is likely high enough that you can include one hard workout and one moderate run per week.
Because of the focus on mileage and general fitness, the base phase is not a time for gut-busting track workouts or exhausting marathon distance long runs. The workouts are short and often effort-based rather than pace based, such as surges, hill repeats, and short tempo or steady state runs.
Surges: In the middle of an easy run, add 5-8 repeats of 30 second surges with a few minutes of easy running in between. The surges should be at a hard effort with a focus on a quick turnover of the feet, but not so hard that your breathing is labored once you return to easy pace.
Short Tempo: After a 1-2 mile warm up, run 2-3 miles at a comfortably hard effort (between 10K and half marathon pace). Cool down with 1-2 miles of easy running.
Short Hill Repeats: Warm up with 1-2 miles of easy running. Find a moderately steep hill and run up it hard for 30 seconds, then jog back down slowly to recover. Repeat this 6-8 times and then cool down with 1-2 miles of easy running
If you are going to gravitate towards one extreme or another, err towards the side of caution and stick to only easy to moderate miles. You don’t want to overtrain when you’re not even training for a race.
How do you structure your base phase training?
What’s your workout today?
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