No, not at all. The pedal force involved (torque) required to grind coffee beans is nothing like the effort of riding a bike because you do not have to overcome ground or air resistance or gravity! You are stationary – parked – and simply pedalling a very smooth, geared transmission to directly turn the grinder burrs. Without the beans there is no experience of resistance at all. When you dose the grinder with beans you feel some resistance at the beginning – and there is a simple technique to overcome this – but then it quickly eases off to a very light feel.
It is a common misconception to relate pedal-grinding to the more familiar effort of using manual hand-grinders: Grinding by hand is very slow because (a) the burrs in hand grinders are about half the diameter of commercial burrs and so have far less surface area for grinding, and (b) operating a hand grinder you only turn the burrs at about 60–80 rpm. Using the Velopresso GR1-Velo pedal-grinder is a totally superior experience and the speed and grind quality is the same as commercial electric grinders. To start with we use large commercial conical burrs – Ø71mm as used in a Mazzer Robur – and then there is the speed (rpm) of the burrs: Your legs are much more suited to the job than arms (and your hands are also left free to prepare the coffee). Pedalling at 100 rpm generates speeds of between 300 and 400rpm at the burrs, and grinding an18g double-shot dose on a Velopresso takes 8 seconds or less, (whereas an average handgrinder might take 1.5 minutes).
Working on a Velopresso machine throughout a working day gives the barista some gentle exercise which is good for your health and keeps you warm on cooler days, but it would not replace a real exercise regime! If you want real exercise go for a swim, run or out on your bike! Pedal-grinding is too easy!