Wooden katanas, also known as bokken, are designed and constructed to withstand the impact and stresses of training and practice sessions. While they are not indestructible, they are generally durable and less prone to breaking compared to other materials.

The durability of a wooden katana depends on various factors, including the type and quality of wood used, the construction technique, and the care taken in its maintenance. Here are a few considerations regarding the strength and potential for breakage of wooden katanas:

1. Wood Selection: High-quality hardwoods like oak or hickory are commonly used to make bokken. These woods offer good strength, density, and resistance to impact. The choice of wood plays a significant role in determining the durability and longevity of the bokken.
2. Construction Technique: The way a wooden katana is crafted can influence its strength. Bokken that are properly shaped, balanced, and reinforced at stress points, such as the handle (tsuka) and blade/hilt junction, are generally more resistant to breakage.
3. Proper Use and Care: Wooden katanas should be used and maintained appropriately to minimize the risk of breakage. Avoid using excessive force, striking hard surfaces, or subjecting the bokken to extreme temperatures or moisture. Regular inspections and maintenance, such as checking for cracks or splintering, can help identify any potential weaknesses and prevent breakage.

It's important to note that while wooden katanas are suitable for training and practice purposes, they are not meant to replace the functionality of a real, sharp-edged katana made from steel. Wooden katanas are designed to provide a safer training alternative and simulate the weight and feel of a real sword while reducing the risk of injury.

Ultimately, the durability of a wooden katana depends on its quality, construction, and proper usage. With appropriate care and maintenance, a well-made wooden katana can withstand regular training and practice sessions without easily breaking.