Here’s an idea:
Create three tables:
Customers
Workouts
LINKER
Linker has two fields:
LinkName (Single Line Text)
Workouts (Link to the workouts table. Allow linking to multiple)
This table gets one record only. Name it “LINKALL”. Every time you add a new workout, add it to this record:
In Customers, add two new fields:
Linker (Link to the Linker table)
All Workouts (Lookup field: Look up the workouts from Linker)
Each customer’s Linker Field should be linked to that one record in Linker. It will then pull in all of the workouts.