is attack on titan (shingeki no kyojin) episode 4 filler?

In the year 850, over two years after enlistment, the 104th Cadet Corps is undergoing a fitness assessment. The cadets are doing a run with weighted backpacks, but Armin Arlelt is exhausted and is scolded by the commandant, Keith Sadies.

Reiner Braun decides to help Armin by picking up his bag. Sadies critiques the overall abilities and teamwork demonstrated by each cadet as they continue the assessment in Titan search and destroy.

Later, the cadets are practicing hand-to-hand combat as Eren disarms Reiner.