The phrase "fuel substrate" refers to the material or substance that can be used as source or basis for a fuel. It is like the ingredients or raw material that can be converted into energy through a process like combustion. Full definition
They found that the ingestion of bananas before and during prolonged and intensive exercise is an effective strategy, both in terms of fuel substrate utilization and cost, for supporting performance. (blog.nasm.org)
The biological explanation is anchored by preferential fuel substrates, which depend on both type of training and duration. (womenshealthandfitness.com.au)
Increase energy by supplying an additional fuel substrate that your body and brain can use immediately and readily. (mpasupps.com)