Why stiffness occurs.
The fate of mankind: Our bipedalism pitted against the pulled gravity.
The supportive muscles of the spinal column that continuously maintain posture become strained and fatigued.
Poor posture increases the strain on varlous muscle groups increasing muscle fatigue
Poor blood circulation (Oketsu)
If the blood is muddy (Oketsu), the supply of oxygen is poor and lactic acid (fatigue substance) is produced, resulting in poor metabolism and stiffness.
Lack of exercise improper BMI* and can make you stiff.
* Body Mass Index
The autonomic nervous system is disturbed by staying up late, stress, and overwork. As a result, peripheral blood flow decreases and stiffness can also occur
Decreased metabolism and increased chronic stiffness in middle-aged and elderly people causes poor mobility.
Areas where stiffness occrurs (causes of back pain, sciatica, knee pain, neck pain, etc.)
(From "Blood Circulation Health Method” by Koki Osugi)