Centennial Park training

[weiyun]

The hill in Centennial Park seemed to have become the focus of our Sat Slowies group with quite a few dedicated riders who just want to ride up and down it for the duration of the ride... What are you guys thinking?!?

Anyway, just so that you guys can explain your bizarre activity on beautiful Sat mornings to your partners and others, below are some data I recorded today.

In summary, the hill is around 533m long, average 5.8% grade with an initial 7.3% rise towards the end of the triathlete field, and a very short kick to 8.1% near the peak. So there you go...

The overall profile of my ride but you can see the multiple small rises that corresponded to the park loop while the 5 regular large peaks represented the hill.



Here's a closer view of the hill's profile.

[matt]

Thats brilliant weiyun, I have been using that hill to test gearing on the fixie, so its great for me to have that data - it gives me a distance and gradient benchmark.

Looks like you had a busy morning, 10 laps and 5 hills? Although is that a short cut I detect on that first climb??

BTW Can you use that record to get the gradient and distance if you do the hill in the other direction (the route that the ride for life took)?

[weiyun]

Nope, no short cuts. Unfortunately with the tree covering, the GPSr sometimes loses the signal, rendering what appeared to be a shortcut. It's much better seen on the plan view. Also, we exited through Paddington gates after a final tackle of the hill. The extension associated with that last peak in that series represented the continuing ride outside the park. The other thing you might have noticed is that the base of the hill seemed to be sinking the more times I ride it. It's actually the altimeter slowly normalizing over time. If I had set my initial altitude at home correctly then it would have been much more stable than what's in the graph.

Yes, you certainly can get the grade in the other direction. Just reposition the markers on the specific segment you want.

Actually, I should correct myself. The 533m distance is the horizontal distance. So the actual distance travelled on the grade is greater by a small margin.

[Simon Llewellyn]

That is pretty funky!

[mikesbytes]

The entire thing is amazing. I'm pleasantly surprised at the level of detail it produces

[weiyun]

Nothing special really. Sports scientists use GPS data all the time. It's even more amazing when you can combine a rider's power output characteristics and various other variables with this data. What it means is that they can fully predict the outcome of a race, or try different hypothetical race strategies and know the likely outcome.

[mikesbytes]

Actually, I should correct myself. The 533m distance is the horizontal distance. So the actual distance travelled on the grade is greater by a small margin.

If a right angle triangle is 533m along the bottom and 31m on the vertical, how long is the sloping side? Anyone young enough to remember maths?

[Kieran]

If a right angle triangle is 533m along the bottom and 31m on the vertical, how long is the sloping side? Anyone young enough to remember maths?


Well it is the square root of the sum of the squares of the short sides, so


L= sqroot ( 533^2 +31^2) = 533.9 meters. Or actually 533.9007398


Or we can work from the gradient, L= 533/cos5.8= 533.9m

One extra meter, ha!

[weiyun]

That critical 1m... You may just bonk in that 1m if you don't do your calculation right.

[mikesbytes]

1 meter could be the difference between winning and not winning

[weiyun]

Seeing what other clubs have done using the park loop, here's something potentially interesting for us to do. How about a time trial up that Centennial Park hill?

[Simon Llewellyn]

we used to ride a handicap...

[T-Bone]

I really should come out one saturday, need to see where exactly this hill is, as i don't remember many hills being there.

[mikesbytes]

Some of us just do laps of the hill, its the sharp lefthand turn after the toilet block.

[Toff]

Interesting hill profile. Almost a constant gradient the whole way. I could have sworn the profile was the other way round (i.e. getting slightly steeper as the climb continues.) but I suspect that that's just my lack of fitness talking.

[weiyun]

Well, there is a slight drop in grade after the initial kick. I am starting to appreciate how significant a one percent grade change is.

[timyone]

man unless you are on a fixie it seems like better training to do a fastish lap between each hill climb.
Matt has also started doing it backwards, which seems more useful for road riders

[weiyun]

man unless you are on a fixie it seems like better training to do a fastish lap between each hill climb.
Matt has also started doing it backwards, which seems more useful for road riders

I think that you'll have to consider that the term "better" will have to depend on your training objective. Loop in the reverse obviously offers a different terrain. But at the end of the day, total elevation climbed is no different b/n the two.