We include these sizing charts as a guide, but it must be emphasised that the way clothing fits is a very subjective matter.

The jersey, shorts and tights fabrics are very stretchy and most people can easily fit in 3 sizes, without it looking wrong or feeling uncomfortable.

Competitive riders will probably want the clothing to be relatively tight and aerodynamic and even when their competitive days are over, they might still prefer tighter clothing because this is what they are used to. More recreational riders might prefer a looser fit.

For this reason the recommendations of the sizing charts overlap a lot - to take into account personal preferences.

Additionally the charts can only be very general guides. When fabric is stretched laterally it shortens vertically.  So a rider who is of a very stout build, might in height be equivalent of a size 3, but in in fact because of girth, might actually  need a size 7 or 8 and the clothing won't look too long. By the same token a very tall but lean rider might, by height alone appear to need a size 7, but actually a size 3 fits very well.

In addition to the above points one should not assume that the jersey and shorts should be the same size.

For example a very lean and fit rider with muscular legs might find he needs a smaller jersey and bigger shorts. On the other hand a recreational rider  with generous proportions, might well find that he needs a much bigger jersey than shorts. Both examples will be correct.

The fabrics for jackets and vests are a little less stretchy and if in doubt it's probably safer to error on the side of larger, rather than smaller for these items.

The above considerations for cyclists also apply to runners.