"Fitness Challenge" on Lassen Peak

Wikipedia tells us that Lassen Peak is  "the southernmost active volcano in the Cascade Range. Located in the Shasta Cascade region of Northern California, Lassen rises 3,500 ft (1,100 m) above the surrounding terrain and has a volume of 2 km3, making it one of the largest lava domes on Earth".

Reason enough to visit this peak in the end of my trip to Northern California climbing Mount Eddy and Shasta . It's just an easy hike (for a mounainieer) - but for many it is a Fitness Challenge* to get to the top!
Officially there's just one route to the summit called "Lassen Trail", a well maintained path around T3. If you attempt to traverse the peak or doing some climbing, get a special permit...

Lassen Peak - a first class outlook in Northern California

Useless to describe the route, you follow the Lassen Peak Trail to the summit and back again, about 5 miles roundtrip and 600m (2000 ft) gain.

Remark 1: I don't get the point about the "Fitness Challenge" - i would assume, that you burn more calories if you're faster? According to the extended table (about 1:15 round trip) I would have burned less than 1000 Calories?!

Remark 2: This report is one of the last of my USA 14 holidays. I had a great stay over there and without the homebase and help of 360 it wouldn't have been as sucess- and joyfull - thanks a lot!