does post marathon recovery run have any meaning?

Every year, April and May are peak periods for hosting marathon events. Unique marathon events come one after another, and some runners, to avoid missing out, often choose back-to-back races. They rush to the next race without having time to rest and adjust properly.

To eliminate the soreness after running a marathon, many people choose to do a recovery run the next day. They believe that a recovery run can effectively solve the problem of muscle soreness. So, is this really the case? Is there any scientific basis for recovery runs? Today, let's explore this topic.

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How did the concept of recovery runs come about?

Before the rapid development of marathon running in China, people's understanding of exercise was relatively superficial, and most views were based on intuitive perceptions.

Because intense exercise leads to a noticeable feeling of muscle soreness and swelling, the greater the intensity, the more pronounced this feeling becomes. Since this soreness during exercise is mainly caused by the accumulation of lactic acid, lactic acid became the starting point of this basic understanding, leading to the concept of recovery runs.

People found that besides the soreness caused by intense exercise itself, muscles would still feel very sore for several days after engaging in an activity that exceeded their usual level of exertion. Naturally, they wondered if lactic acid was continuously accumulating in the body. So, how could this soreness be eliminated? Some chose to overcome the soreness and continue exercising until it was completely gone. This is the origin of the recovery run.

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Lactic acid actually disappears after half an hour

The soreness during exercise is indeed caused by the accumulation of lactic acid, which is also a major reason for our physical fatigue. However, regardless of the duration or intensity of the exercise, or whether you stretch afterward, the lactic acid accumulated during exercise is completely cleared within half an hour after the exercise ends.

So where does this lactic acid go? It certainly doesn't get expelled from the body. Have you ever felt acidic substances being expelled through sweat, urine, or breath? Obviously not.

First, most of this lactic acid is completely broken down into water and carbon dioxide, releasing energy. Secondly, some lactic acid is converted back into glycogen in the liver and stored. The entire process of lactic acid clearance takes about 5-10 minutes, and at most, no more than 30 minutes.

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Muscle soreness is the fundamental reason

Since it's not lactic acid accumulation, why do we feel muscle soreness for several days after a marathon? This phenomenon, where muscle soreness is not noticeable on the day of exercise but becomes apparent the next day, is called delayed onset muscle soreness (DOMS).

Typically, delayed onset muscle soreness appears a few hours or a night after exercise, showing a delayed onset characteristic. This symptom also disappears slowly, taking as short as two to three days or as long as 3-7 days to fully recover.

The mainstream view currently is that post-exercise muscle soreness is mainly caused by micro-damage to the muscles. In other words, the exercise exceeded the normal load the muscles could handle, such as running a marathon, challenging new distances, or new paces.The body's inability to adapt leads to micro-damage in the muscles. During the repair process, inflammation occurs, causing muscle soreness.

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Is there any point in doing a recovery run after a marathon?

Some runners might ask: Since there is no lactic acid to expel, is there any point in running the day after a marathon?From the above, runners should understand that lactic acid cannot accumulate in the body for a long time, so the concept of expelling lactic acid is non-existent. Therefore, the idea of a recovery run is a misconception that has been passed down for centuries.

After a marathon, especially the first one, the microstructure of the muscles is already damaged. The body will start the repair mechanism, and what you need to do is rest. Continuing to run can easily irritate the muscles, delaying repair, and even worsening the damage. This is why some runners still feel muscle soreness the day after a recovery run.

Some runners even mistakenly blame themselves for not running long enough during the recovery run to achieve the desired effect, and further increase their exercise volume. This leads to repeated micro-damage to the muscles and more severe inflammation. Therefore, a recovery run is not a standard post-marathon practice; resting after a marathon is the best recovery measure.

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Why do some people feel that recovery runs are effective?

Since you should rest the day after a marathon, why do some runners feel that their muscle soreness is indeed reduced after a recovery run?

On one hand, low to moderate intensity exercise can provide immediate relief from muscle soreness when it is very noticeable, but this effect is very short-lived. After an hour or two, the soreness will return. Additionally, for seasoned marathoners, muscle soreness is only mild on the second day and naturally disappears by the third day. This is not due to the recovery run but the natural recovery process of the muscles. If you do a recovery run on the second day after a marathon, you might mistakenly attribute the relief to the recovery run.

Therefore, recovery runs can at most be understood as active recovery. Active recovery refers to doing some low-intensity exercise after high-intensity exercise to promote recovery and reduce fatigue. However, there is currently insufficient evidence to prove that recovery runs help eliminate delayed onset muscle soreness.

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After a marathon, proper rest is key

Muscle soreness the day after a marathon is a normal reaction of the body to the load. It is difficult to eliminate it fundamentally. Without any intervention, your body can naturally recover in a few days, and after recovery, your body will become stronger.

This is why first-time marathoners experience severe muscle reactions, but when you participate in your second or third marathon, the muscle reactions are significantly reduced. Your muscles have formed a memory and become stronger. As your ability improves, you can handle marathons better, and delayed onset muscle soreness occurs less frequently.

A marathon is an extreme sport that causes significant fatigue to the body. Generally, it's best to rest for 2 weeks after a full marathon, at least 1 week. After a half marathon, it's best to rest for 1 week, at least 3-4 days. Don't worry too much about losing endurance; the endurance you've built up won't disappear quickly.