We had a 35 year old morgan gelding who was very active, and even though he wasn't a real hard keeper, we still supplemented his feed. We gave him a coffee can full of equine senior, half to a full coffee can of rice bran, and a half a coffee can of wet cob or dry cob depending on what the store had at the time, as well as 4-flex for joints. The grain was in addition to about 20lbs of alfalfa a day. He always did well on those feeds. You just have to be careful. The high protein, and lots of grain worked for him because he got out almost every day, did low jumping, barrel racing, 3-4 hour long trail rides, so he was worked pretty hard. Its always free to talk to your vet, so I suggest asking your vet what he/she thinks, and go from there. They have good suggestions. That was how we figured out what to feed my mare, and the morgan.