Base Building Phase of a Distance Program

What is it and why is it important?

At the beginning of a running training program, we need to work on building a base of miles. We are also building our commitment and putting structure in place. We focus on adding volume only; adding volume and speed at the same time increases the risk of injury. These runs should be done at 60-70% effort (maximum heart rate) and at a conversational pace. We increase our mileage slowly (by no more than 10% per week) so that our bodies have the chance to adjust to increased demand. This is especially important at our pace because we take more time to run the distance, which means more contact with the ground, more time in the heat and greater hydration needs.

What is happening to our bodies during this phase and what are the benefits?

We are slowly building intensity to boost our fitness level without getting burned out by increasing miles too fast. Our bodies are going to adapt in the following ways:

  • Left ventricle in the heart expands, the part of the heart that sends blood out to the body (stroke volume increase)
  • Resting heart rate will decrease
  • Red blood cells increase, which carry more oxygen to the rest of the body
  • Blood plasma volume increases, putting more liquid in the blood so that it can move more freely
  • More and larger mitochondria are built--this is the power plant of the cell and where the aerobic energy is liberated and builds endurance
  • More capillaries, which are the smallest arteries delivering oxygen from the blood to the muscle cell
  • Increased storage of fuel in the muscle cells (glycogen storage)
  • Insulin sensitivity goes up, the hormone that pushes glucose into the muscle cells
  • Muscle fiber alterations--slow twitch are better at handling aerobic performance; fast twitch gain more endurance
  • Neuromuscular system is more coordinated
  • Stiffening of the connective tissue so we are more springy and have better energy return
  • Improved running economy in how oxygen is used, increasing aerobic conditioning
  • Muscles, tendons, ligaments and fascia get stronger
  • Change in perception of discomfort
  • Reprogramming of our conscious and subconscious mind
  • Stress response decreases
  • Increased energy as the weeks progress
  • Less accumulation of lactic acid and carbon dioxide
  • Lower body fat and less fat under the skin

The most important benefit here is increasing aerobic capacity and conditioning. As we increase distance, our body relies on aerobic energy vs. anaerobic energy. This takes time and discipline and that is why we spend six weeks focusing on the base. Developing our aerobic capacity is what is going to get us through the longer runs. We are also teaching the body and mind to adapt to a specific stress until it is no longer stressful and then moving onto a different stress in the next six weeks. Here is a nifty chart showing the splits of aerobic vs. anaerobic energy contribution for some popular distances.


What else should we focus on during base building?

One of the basics of good form running is cadence. Cadence is the number of times our feet hit the ground per minute—basically leg turnover. We are going to focus on a cadence of 175-185 steps per minute. Now, this may sound really fast, but this has nothing to do with pace. You can run a 6:00 mile and a 12:00 mile at 180—the only thing that changes is that your stride lengthens out the back the faster you go. Why is this important? Because the longer you are in the air, the harder you will hit the ground on landing and that causes landing shock to your arches, ankles, knees and hips. Sticking to a cadence of 180 results in quicker and lighter steps, which equals less injury and better efficiency.

We should also incorporate some cross training during this phase. It is an active rest for the running muscles but we are getting added cardiovascular benefits.

What should we expect on an easy run?

I actually like to think of this run as easy to moderate. Easy because we aren’t gasping for breath, but moderate because we are challenging ourselves to a certain extent. The easy run is a shorter run—our longest easy run will be 7 miles. In a few weeks, we will incorporate some drills into the run.

What should we expect on a long run?

The long run is a steady run at easy conversation pace. The long run should be no more than 1/3 of our total weekly mileage. It helps our bodies adapt to fluid loss, glycogen depletion and we will rely more on fat as fuel (yay!). We build up the long run slowly and the benefit is that it is moderately challenging and our bodies should adapt and recover quickly. We will also increase our emotional and psychological ability to handle discomfort on longer runs.

What about rest and recovery?

Rest is a very important component of base building and is built into the schedule. Our bodies need time to recover. Nutrition plays a huge role in recovery. Eating lots of vegetables will help speed up our recovery. Why is that? For one, blood is drawn to the stomach when we eat foods that are not easily digestible. We want the blood to go to the muscles so eating foods that pass easily through the body is ideal. We need to eat food that easily turns into energy that we can use and is nutrient dense. The best foods for this are raw, high alkaline (green veggies), whole foods and non-stimulating foods.

Final thoughts

We are early in our training program and you may be feeling some fatigue. Hang in there—it will get easier as the weeks progress. Remember that most of us are adding miles to what we had been running and we may experience a little fatigue. It will pass! Just put the time and the miles in and soon a 5 mile run will seem easy.