Digging 

Purpose – Strengthens forearms and shoulders. Also great for wrist and toe strength.  
 
Criteria – Digging evenly with both front feet. 
 
Placement of reward – Sometimes to get digging started you can bury food in the towel or sand. Once they have started digging without needing that and it's put on cue then I just say yes when I am going to reward them and want them to stop digging. 
 
Training tips –This can be done with a towel or in sand. You can bury food or toys under a towel or in the sand and encourage them to dig to find it. Say yes when they are digging and reward them. Gradually add more duration to it. If they only dig with one leg mostly then try different things to help them to use the other more too. 
 
Increasing difficulty – Longer duration on time of digging