
Powercal Powermeter: More than just an HR strap
Its been quite some time since I’ve written something in my blogsite. Simply put, I have been in hiatus for several months, avoiding racing. Timex 226 2011 squeezed out my multi-sport juice dry, leaving nothing for 2012. Coupled with a daughter getting into college, the best option for me was to semi-retire from competitive racing and live a normal and fit life, away from the rising costs of race participation and training expenses, but within the confines of a multi-sports athlete’s sanity.
When I decided to wear my lycras and shoes with elastic laces again, I needed to give myself extra motivation to go out and burn calories. Like any other big boy, I needed a new toy to play around with during my comeback. But what? I have basically everything I needed for training.
Then our ever-reliable sponsor, Bikezilla, offered the Powercal.
I have never trained based on power before, and that was one aspect of the sport I want to venture in. How many watts of power do I generate during a bike ride? What was my functional threshold power or FTP?
The Powercal is a power meter which computes one’s power output via the heart rate. The device moves away from the direct force applied power computation by using an algorithm based on thousands of averages ( between heart rates and power ) from different athletes and coming up with a formula on how this can be applied to measure an individual’s power whoever he may be, well, except Lance Armstrong and the other tour riders. People who use crank or hub based powermeters were skeptic of the device, asking how it could be possible. Several reviews found in the internet provide direct comparison between a Powercal and an actual powermeter and have found it to be giving readings of +/- 15w over or under what actual powermeters read. Most have found it consistent.
As someone who does not own a powermeter, Powercal should be useful to me, without skepticism as a result of actual powermeter readings. With its price only a tenth of what a powermeter costs, it shouldn’t be a painful investment.

Just finished setting this toy up. I now have an indication on how much power my legs can produce. Thank you Bikezilla!
The Powercal pairs with any ANT+ compatible device/ display. My Timex Ironman Global Trainer paired easily with it. Felt great to have another field on display with values in it. Pairing is done via making your ANT+ device scan for powermeters. Once it detects the Powercal, just pair it and you’re on your way to training with power.
The first thing one needs to do in training with power is to determine what his functional threshold power or FTP is. FTP generally means the maximal power output one can generate in one hour. It is NOT the average power though. For better explanation, click on the link below:
I chose the 20-minute all-out approach and cranked a 20-minute time trial on my bike trainer then got 95% of the result -= FTP.
In the 20 minutes of TT, I averaged 208 watts of power which should give me a one-hour FTP of 198 watts. So what is the relevance of these FTP numbers?
If I have an FTP of 198 watts and continuously do 220 watts in a race, I would run out of power even before the race ends…that simple. Your FTP is your guide to how much power YOU CAN use in a race without running on empty and bonking just before you finish. Its the power you can sustain. If there are two sprinters with both having FTPs of 300w, with one going 400w at the start of the race and the other sticking to 300w, the former will be ahead before the first half of the race and slowly fade at the other half while the latter will be consistent and catch up with the former before the end of the race. Confused? Read the link I posted above, again.
FTPs are also used to compute your power to weight ratio. Having similar FTPs doesn’t mean two persons have similar strengths. Power to weight ratio is computed as FTP / Weight (in KGs ). Let’s compute for mine:
FTP: 198w
Weight: 82kgs
Power to weight ratio: 198w/82kgs = 2.41
The magic number is 4, which means I am far off from being an efficient cyclist…Ughh! No worries though, if I want to increase my power to weight ratio, I just have to ride hard…a lot.
Prior to Powercal, all of the above can only be determined with the use of a power meter, which costs an arm and a leg. Previous mindsets were that only the “elite” athletes would invest in such expensive equipment as they need to continually monitor their progress, in all the aspects of their training. Powercal made training with power accessible even to BOP ( back of the pack ) athletes like myself. Costing Php 5,800.00 for the version which includes a speed sensor, and Php 4,800.00 for the version without, Powercal is about a tenth of the cost of “real” powermeters. Not bad eh?
But there is a downside to using HR based power meters than its direct force applied brother: There will still be readings after you stop pedaling because your heart still keeps on beating.
Also, since power is based on HR, the minutest change in your heart rate is translated either to an increase or decrease of power even if you’re pedaling with the same force. For example, my heart rate when on aero position is 141bpm with a power of 220w, once I get on the hoods but still pedaling the same, my heart rate drops to 140bpm as I can breathe easier, my power would also go down to 177w…all these changes with me pedaling with the same force. In real power meters, this doesn’t happen.
The geniuses at CycleOps claim that Powercal is NOT as accurate as PowerTap or other real power meters, BUT it gives a good estimation of an individual’s power…I strongly agree! Having had no experience in real powermeters give me the confidence to trust in Powercal as I have no other device to compare its readings with. If Powercal says that I churn 200 watts of power, then so be it. My target for improvement will be based on it still, not with a real powermeter. The issue with those who have crank or hub-based power meters is that they keep on comparing the results of both, to which no similarities will be found, except probably for the trend lines of the data. If Powercal gives a reading of -15w vs. a power meter consistently, then one must focus on its consistency, not the actual numbers it reads.
Powercal is one budget-constrained athlete’s greatest investment. It will give his training a whole new slew of possibilities in order to improve his performance. The device is easy to use, easy to maintain, comfortable to wear and is reasonably priced. You can use it on whatever bike you have, interchangeably. There shouldn’t be a reason why you don’t have one if you’re a cyclist or a triathlete who wants to improve on each race he joins. In the recently concluded Tour Of Matabungkay, I survived a 130km road race with more than 20kms of climbs, peaking at 2,000+ feet above sea level, by merely keeping within my FTP, using a Powercal. Its how useful it is.
Powercal is available at Bikezilla, though its increasing popularity makes it always on limited stock.
Deo P.




























































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