What makes speed skates faster?
A combination of technical details makes a speed skate faster than the usual fitness/recreation skate. Here’s the low down on them, in English.
BOOT
Stiffer boot body and base – Speed skate boots have minimal cushion, only super-compact cushions where it matters. This reduces the amount of energy lost to soft linings. Also the base is made of high-strength lightweight materials like carbon fibre or fibreglass, maximising the power transfer from the base of your foot through the boot to the frames.
Surer fit – Compact technical cushioning in the boot ensures that it wraps around your feet firmly. If there’s something that “fits like a glove” on your feet, it is a speed skate. Some speed skaters demand so fit accuracy that they skate without socks. The sure grip allows the wearer fine control over the skate, making it respond to every little movement faithfully. Also, edge control (whether the skates are vertical or angled with respect to the ground) can be controlled to the millimetre. In fitness/recreation skates, the feet may shift slightly within the boot because of the easy-going cushioning. In speed skates, there is zero shift of the feet within the boot. Some speed skates ar built with heat-mouldable materials allow heat moulding to closer match the wearer’s feet shape. Other manufacturers offer perfect feet with custom boots by building them from scratch around a cast of the skater’s feet.
No ankle cuffs – less restrictions on the ankle means you can flex them forward and laterally to a greater extend. Forward flex allows a deeper knee bend for better aerodynamic posture, lateral flex allows your stroking feet to get closer to the ground for that extra few inches “power zone“ in every stroke.
FRAME
Stiffer frame – Speed frames are usually made from aircraft grade aluminium, and in some cases, military grade magnesium alloys. These are much stiffer than plastic/composite frames, thus increasing the power transfer from the base of the boot to the wheels and the ground. Some frames have ribbed structures and cross beams along the body, making them even stiffer.
Longer wheelbase – Wheelbase refers to the length between the axels of the first and last wheel, which is also the length between where the first and last wheel touches the ground. Speed frames come in varying lengths, and are generally at least an inch or more longer than fitness/recreation skate frames. Longer frames translate into lower cadence (number of strokes per unit distance). This means you repeat your strokes fewer times (but with slightly greater intensity) to cover the same distance compared to a standard length frame. Fewer strokes mean higher efficiency. This is like using the higher gears in a car, which are more efficient over long distances. Longer wheelbase also means less lateral drift. That means you can stay coasting on each feet much longer and more easily compared to a shorter frame.
Lighter weight – speed frame manufacturers strive to use materials as efficiently as possible to maximise the strength-to-weight ratio. This reduces the amount of weight you have to carry during the race. Combined with the fact that frames are made of lightweight metals, it reduces fatigue and increases speed to some extent, especially over long distances.
WHEELS
Harder wheels – This is where the rubber, (polyurethane actually) meets the road. Harder wheels, as in the case of stiffer boots and frame, means higher power transfer. Harder wheels flex and compress less than softer ones. This means less energy is wasted flexing the wheel. More gets transferred through it and ends up as pressure on the tarmac where it becomes propulsion. Multiply that by the number of strokes you make over the kilometres… you get the idea.
Larger wheels - These translate into improvement in a few areas. Firstly, a larger diameter makes it easier for the wheel to turn the bearing. Just like a wrench with a longer handle can turn a stiff nut more easily than a shorter one, greater distance (between the road surface and the centre of the bearing) exerts more torque on the bearing, turning it more easily. Secondly, larger wheels have to rotate fewer times to cover the same distance as a smaller one. This means the bearing can spin at a lower RPM (rotations per minute) at any given speed, incurring less friction in the bearing and hence cost less energy. Larger wheels also have the advantage of rolling over rough ground and small objects (like twigs and the odd chip of gravel) with more stability.
Wheels with sharper profile – Large diameter wheels also allow manufacturers to taper the wheels to a sharper edge. Sharp edges means less surface area in contact with the ground (when the wheels are vertical). This reduces drag just like how tires on road bikes (think Tour de France bicycles) reduce drag by being very thin. Less drag means higher efficiency, which translate into less fatigue for the skater over long distances. Besides reducing drag, the shape of race wheels is also designed to increase in ground contact area when it is angled close to the ground. Increased contact area means more friction (hence grip) when you need it in a tight corner. So large race wheels offer minimum friction on straightaways and maximum grip around corners.
Given all the above technical advantages, speed skates are always faster, everything else being equal. Are you ready to hop into a pair? []
Got questions about this story? Or see something that is wrong and needs to be corrected? Contact us at edmund@skateline.com.sg