I’ve been fortunate enough to receive a loan of an Airhub Pro since December, courtesy of Guy Kalma. This training device, for those unfamiliar with it, applies resistance dynamically while riding via an electromagnetic brake in the hub. The Pro model comes with 3 modes; off, 1 and 2. 1 applies one watt per km/h in resistance and 2, two with both modes capping at a maximum of 100 watts of resistance. Below I’m going to detail how I’ve used it and some of my thoughts.
Use case 1: Training with a less powerful group or partner
It goes without saying that there’s varying builds and strengths in cycling. Rarely will a pair of riders be equally matched. Even if riders are matched, for those on a regimented training plan, the demands of a days training may be quite different. By selecting an appropriate amount of resistance with the Airhub, one can train with others who are not presently putting out as much power and get a quality workout, suited to their own needs.
On a gentle Christmas club ride I dialled the hub to 2 so I could keep some pressure on the pedals. On a small mid week bunch ride I keep the hub on 1 in order to provide additional training stress. During this ride it forces me to ride deep efforts to move to the front and into a solid threshold level while pulling. In the pace line it keeps me firmly in tempo, allowing the ride to have a strong aerobic impact and draw some mixed efforts out.
In training for the Melbourne to Warrnambool I picked up a new training partner in Serene Lee, also prepping for the event. Generally, it’s difficult for men and women to mix training one on one but the resistance of the Airhub facilitated this quite well. I was able to adjust the resistance, rather than my riding such that we were riding sessions of similar make-up.
Use case 2: Base training
The primary use I had in mind for the Airhub when I looked into it was long, endurance base training. The key utility here is in keeping effort steady and high. The device can help with this on several fronts.
While stuck nearer the city, some level of traffic can be expected unless one subjects themselves to exceptionally boring loops or the trainer. When encountering traffic, a dialled up ‘Hub means that the power can stay up at lower speeds. This assists while navigating motor traffic or on the shared paths. It also has the effect of keeping speeds a bit more sociable on these paths. The speed limiting factor can also be exploited to get just the right amount of effort in on a time limited loop; I’m often fitting training in between errands and this can allow me to vary the time to complete a circuit to better fit my needs. Finally, this speed limiting factor provides a boon to motivation in my opinion. I’m much more inclined to press on at a high tempo to keep the speed at a stimulating level. The desire to add 50w for a couple of km/h at 40km/h as opposed to adding 5km/h at 30km/h is much lower.
When it comes to leaving the city limits, there are some other benefits. While completing large, hilly loops aiming for a power target there can often be a lot of variability introduced by resistance increases/decreases, up and down hill respectively. While this variability can be very useful in certain kinds of training I’m of the mind that it’s not at it’s most helpful while working on base. The hub’s resistance mitigates this and produces a flatter effort. Resistance from the unit decreases uphill and rises downhill, producing a fairly steady tempo. This is the only mode of resistance for the Pro, and the “full” Airhub has similar options available.
Use case 3: Aerobic intervals
This has some overlap with the qualities I described under the previous section. The ability of the Airhub to level efforts and apply resistance downhill makes it suited for high aerobic power intervals. Personally, I’ve nearly sworn off stationary training sessions and prefer to do intervals on the road. My main training circuit for this is in Perth’s Kings Park. The loops I create in here are basically half uphill, half downhill with a little bit of flat ground.
When riding threshold level intervals, speeds can get quite high and for sustained duration (8-20 minutes at a time). Concentration can lapse, lowering speed in this instance is beneficial for safety. More importantly, for a couple of minutes downhill it can become difficult to apply sufficient power to maintain an appropriate average without resistance. The Airhub makes 350w+ downhill stretches readily attainable without spinning out or reaching speeds too high for conditions. The resistance reduces on the uphill with the Pro model, which keeps these portions at a speed I find stimulating while still allowing for a degree of variability; I ride my threshold intervals as perpetual over-unders, which is part of why I have a preference for doing them on the road.
Similarly to the threshold use case, VO2 or low anaerobic level intervals are faster still. In the lead up to the Tour of Chiangrai in December 2018, I was targeting an 8.5 minute effort of 460 watts. To this end, I was training either side of this duration with some classic VO2 work (this didn’t require the hub as the efforts could be completed as short hill intervals with a roll down) and some longer efforts of ~410-430 watts ranging from 8-10 minutes. The latter is a case that amplifies the needs mentioned in regards to threshold work.
I’ve found a number of uses for the Airhub since I’ve had it at my disposal. It’s enhanced my social riding, as quite often it’s hard to find a suitable partner or group for the demands of training…some of them may think you’re insane, though the Airhub might not fix that. It’s facilitated some quality work on a tight schedule. It’s allowed me to have more precise control over the level of effort I’m doing on the road. I suppose it’s also kept a couple of furious cycling charges at bay. An Airhub isn’t inconsequential in cost but if you’ve got some reasons to use it, it’s an excellent tool to have at your disposal and can provide some small lifestyle changes in addition to altering the quality of your training. The price is well justified for it’s target market. I’d thoroughly recommend it to anyone with a list of needs like the above.