The choice of material for training swords depends on factors such as safety, durability, weight, and cost. Here are a few common materials used for training swords:

1. Wood: Wood is a popular choice for training swords due to its availability, affordability, and versatility. Hardwoods like oak, hickory, or ash are commonly used as they offer durability and can withstand the impact of training sessions. Wooden swords, such as bokken, provide a safe and effective option for practicing martial arts techniques.
2. Synthetic Materials: Synthetic materials like polypropylene, nylon, or rubber can be used to create durable and lightweight training swords. These materials are often designed to mimic the weight and feel of real swords while providing enhanced safety during training. Synthetic training swords are resilient and less prone to damage compared to wooden swords.
3. Foam or Padded Weapons: Foam or padded training swords are frequently used in sparring or contact-based martial arts disciplines. They are typically made of foam or other soft, impact-absorbing materials, encased in a fabric cover. Foam weapons allow for realistic training with reduced risk of injury.
4. Aluminum or Plastic Alloy: Some training swords are made from aluminum or plastic alloy. These materials offer lightweight options that can withstand regular training use. They may have a metal-like appearance and provide a more rigid feel compared to foam or wooden swords.

The best material for a training sword depends on factors such as the specific martial art, training objectives, safety requirements, and personal preference. Each material has its own advantages and considerations, and the choice often comes down to finding the right balance between safety, functionality, and durability for the intended training purposes.