Of course! Assign a workout or program to yourself, then access it from My Training Log to start your workout. Your results will appear in the main Calendar and your personal calendar in My Training Log.
Make sure you've assigned exercise properties (sets, reps, weight, etc.) to every exercise in their workout. Even if you don't assign a specific value, the exercise still needs a property for your client to enter a value. If you make these changes to their workout or program template, make sure to un-assign and then re-assign it to them so they have the updated workout.