Don’t worry, we’re not back in the 60’s. To me, LSD means long slow distance. I always get funny looks when I direct my team that’s driven to be faster that they are going to, “Run slow today.”
You can practically hear the reaction: “Coach, aren’t we here [at practice] to get faster? I can run the distance today much faster than you want! Let me run fast. Please?”
Far too often do distance athletes turn long runs into negative-splitting or tempo runs. 14 miles at 6:30/mi sounds so much cooler than the 7:35 they were supposed to run. I was one of those athletes. Chasing down any guy in the group who dared to half-step the pace. Before you knew it, we were in full flight, waiting for the next teammate to crumble from our blistering pace. Although quite confidence-boosting, this was neither the time nor place.
As I began to understand and apply my education, I began to wonder why my coach would not rein us in? What pace is best for the body? What is the desired outcome from today’s run? I felt that was a really important piece missing from our training. I promised myself if I ever coached it would be with thorough instruction.
The goals for LSD runs are increased mitochondrial density, capillarization, and structural gains; in both connective tissue and our bones. In contrast, higher intensities of physical activity put too much stress on the body’s internal environment. LSD also offers a regenerative quality, flushing out and realigning muscle fibers. I feel it is easy for most to relate to the basic idea: back to back to back hard runs wear down the body.
But what, you may ask, am I getting out of LSD? First of the adaptations would be increased number of mitochondria. Remember back to your high school biology class? Mitochondria are the power factories of the cells. It is their job to convert resources into energy through a series of chemical reactions. Let’s skip nearly all of the chemistry, for now. The one thing you need to know is that these chemical reactions require oxygen.
Running slow puts demands on the mitochondria, stimulates them, and stresses the body to make more. When energy needs are high for a long period of time, mitochondria will grow and divide. It is theorized that the particular enzyme responsible for triggering mitochondrial fission, AMPK, is not activated until the demands exceed the existing cells’ capabilities. Hard running switches the effort towards anaerobic metabolism (without oxygen). Anaerobic metabolism takes place in other parts of the cell and does not involve the mitochondria. That, of course, limits any stimulus of them. Anaerobic metabolism is also unsustainable therefore can not be performed long enough to stimulate mitochondrial development.*
*More research is suggesting High Intensity Interval Training (HIIT) can increase mitochondrial density. I am still hesitant to agree with the research. The information is too new. Just know HIIT is completely different than doing your 70 minute run as hard as you can. Explosive, fast training also leads to injuries much sooner than LSD.
Endurance athletes want MORE mitochondria. More mitochondria will result in higher aerobic metabolism output. In running terms, this translates into running faster at an easier effort. For example, a heart rate of 150 bpm produced an average of 8 minute pace. With LSD training athletes should begin to observe 150 bpm will soon be 7:45, 7:30, etc.**
**Eventually this linear efficiency does not continue at the same rate and begins to level off. This is why it is important to train/stimulate other energy systems.
With all of that aerobic energy production in the mitochondria, the cell is going to need a steady supply of oxygen, nutrients and waste management. A consistent aerobic exercise routine causes the human body to develop new blood capillaries in otherwise vacant areas. The result is a body more efficient at mobilizing resources and clearing waste.
This adaptation tends to occur further into a long exercise bout (75+ minutes). If an athlete is running too fast, odds are he or she will not make it to the duration of exercise necessary for capillarization to occur. Slow and steady wins the race of capillarization.
The final benefit of LSD runs is structural gains. Pretty easy to understand. The steady, moderate pounding LSD induces can increase the body’s work capacity. The bones become denser, the tendons tauter and muscles stronger. This is a slow adaptation that requires moderate, steady application of stress to avoid injuries: time on your feet.
Thank you for reading my brief overview of why running slower will make you faster in the long run (pun fully intended).