So, the balls, peanuts, donuts, and discs are commonly used in canine rehab and in canine fitness training protocols. Is there research to back up their use? Well no! However, I found an interesting (and I think, related) article from humans!
Gibbons, T. J., & Bird, M. Exercising on Different Unstable Surfaces Increases Core Abdominal Muscle Thickness: An Observational Study Using Real-Time Ultrasound. Journal of Sport Rehabilitation, 28(8), 803-808. (2019)
What was the goal? To evaluate abdominal muscle activity while doing isometric exercise on stable and unstable surfaces.
How did they do it? They took 30 young, healthy adults and had the perform 3 isometric exercises on 1) a Pilates table, 2) a foam roller, or 3) an Oov. (I looked that up… and between us, I think it looks a little ‘dirty’.) Then they used a real-time (diagnostic) ultrasound to measure transversus abdominis, internal oblique abdominis, and external oblique abdominis thickness.
Results: Core abdominal activation was greater on the foam roller than the Oov and Pilates table during crook lying (bilateral leg support). Both Oov and foam roller elicited greater contralateral transversus abdominis and internal oblique abdominis thickness than the Pilates table during tabletop and straight leg raises (unilateral leg exercises). For transversus abdominis only, the foam roller elicited more muscle thickness than the Oov during straight leg raises. The Oov was rated more comfortable than the foam roller.
Conclusion: So, these researchers determined that this supported progressing exercises from flat stable surfaces to more unstable surfaces.
So, I think we can extrapolate that in our canine practices. So, to start and exercise regimen for the abdominals, a flat surface is likely easier, and thus a better place to start. Then as the patient becomes more successful with the exercise, he/she can be progressed to an unstable surface. In doing so, the abdominals should be facilitated more!
There you go! A cool little human study that can validate your canine exercise prescription choices!