Are your feet too heavy to run when jogging? Lactic acid accumulation is the key

Lactic acid is a substance produced when glucose, which is the body's energy source, combines with oxygen inhaled into the lungs and burns together. During intense exercise, if sugar and oxygen are not completely combined, resulting in incomplete combustion, a large amount of lactic acid will be produced.

The blood lactate value is expressed in mmol/L (=mM). When not exercising, the blood lactate level is approximately 1.0 mM/ℓ. If this value exceeds 4.0 mM/ℓ, it is in the state of anaerobic exercise mentioned above.

During a full marathon, the accumulation of lactic acid will affect the degree of muscle fatigue. In other words, you need to move forward at a speed that does not accumulate lactic acid (pure aerobic exercise), or train to run at a certain speed that does not accumulate lactic acid. If you continue to move forward, your performance will improve.

If you want to train scientifically, there are machines on the market that can measure your lactate level by taking a little blood from your finger. After an intense workout, it's a good idea to check your blood lactate levels. By measuring the lactic acid value, you can determine whether your training is intense or relaxing.

The reason your feet feel heavy is lactic acid.

If lactic acid accumulates in large quantities, what kind of impact will it have on the body? Runners must have had the experience of running until their feet become heavy and their whole body feels tired. As lactic acid accumulates, our muscles lose flexibility and become stiff. This prevents the muscles from contracting and can cause the feet and body to feel heavy.

During the competition, we try hard to push our heavy feet forward, but this can easily turn into a stiff running style. With this rigid running method, even if you speed up for a short period of time, you won't be able to sustain it. In order to avoid accumulating lactic acid before your running form becomes rigid, it is important to control your running form and speed.

The day after a competition, your legs will feel sore, and accumulated lactic acid is one of the factors. The way to prevent muscle soreness is to promote blood circulation and eliminate lactic acid accumulated in the muscles. After the game, a thorough workout or a long bath can help eliminate lactic acid, so you might want to give it a try.

Training to improve lactate threshold

There is an exercise that can minimize the accumulation of lactic acid. This is called "LT training". "LT" is the abbreviation of Lactate Threshold, which means "lactate threshold".

Coach Ohgo Eiji of Kanagawa University, who won the championship at Hakone Ekiden in 1997 and 1998, is an authority on this training theory. Kanagawa University attracted much attention in Japan overnight after it successfully adopted this practice.

Specifically, what kind of exercise is this? The lactate threshold refers to the exercise load at which lactic acid begins to accumulate rapidly. In running, the speed (pace) at which lactate begins to accumulate is the lactate threshold. To correctly understand your lactate threshold, you must run at various paces and take blood samples at each time to measure the lactate value at that time. In order to improve the lactate threshold, it is recommended to do pace running exercises within the limit where lactate begins to accumulate.

(220 - age - resting heart rate) × 0.5 + resting heart rate

Although it is not easy to measure the lactate threshold, you can use the heart rate, which is highly correlated with the lactate threshold, as a reference benchmark. As long as a heart rate monitor is installed, everyone can know the speed of LT. Please refer to the above formula for the algorithm.

After using this formula to calculate, I found that my lactate threshold (LT) pace is: 119 heart rates per minute. This is the level of load required for jogging at the appropriate pace.

This article is from Yuanliu Publishing's "Starting from Walking, a Complete Guide to Running a Marathon in Less Than 4 Minutes"