The best sword for training depends on the specific goals, training style, and preferences of the practitioner. Different types of training swords offer various advantages and cater to different martial arts disciplines or training needs. Here are a few common options:

1. Synthetic Training Swords: Synthetic training swords are typically made from durable materials like polypropylene or nylon. They are lightweight, affordable, and resistant to impact. Synthetic swords are widely used in martial arts training, historical European martial arts (HEMA), and stage combat due to their durability and safety features.
2. Wooden Training Swords: Wooden swords, often made from hardwood such as oak or hickory, provide a more realistic weight and feel compared to synthetic options. They offer an authentic experience while still prioritizing safety during training. Wooden swords are commonly used in various martial arts, including kendo, aikido, and kenjutsu.
3. Foam Padded Swords: Foam padded swords are designed for safer contact sparring and practice. They feature a core made of a flexible material covered with foam padding. Foam swords are commonly used in LARP (Live Action Role Playing) events, stage combat, and recreational swordplay, offering a balance between safety and realism.
4. Blunted Steel Swords: Blunted steel swords, also known as rebated swords, are specialized training weapons that closely resemble historical swords but are modified for safe combat. These swords feature dull edges and rounded tips, making them suitable for controlled sparring and historical reenactments. They provide a more authentic experience and feedback compared to synthetic or foam options.

When selecting a training sword, it is important to consider factors such as safety, durability, training objectives, training partners, and the specific requirements of your martial arts discipline or training style. It is recommended to consult with instructors, trainers, or experienced practitioners in your specific martial arts community to determine the most suitable training sword for your needs.