"It has taken off. Accessibility has exploded. There's a large amount of misinformation around the supplement industry," Lendrum said. "Aside from anti-doping there's also health and wellbeing risks.
"It's not uncommon for products to have ingredients that aren't listed. It's very much a buyer beware scenario. That's why at New Zealand Rugby, and together with the Players' Association, we've taken a position on the use of supplements by young players, and that's we don't support it.
"Supplements have a place in a fully resourced high performance environment but nowhere else so it is concerning. The research DFS have conducted with the University of Otago into the attitudes of first XV players in New Zealand, whilst two or three years old, definitely displayed some concerning feedback.
"We understand why they have taken this step and it's incumbent on DFS and schools to deliver the education to minimise the risks."
One major driver believed to be behind the use of supplements in schoolboy rugby is the intense competitiveness now prevalent that stretches from recruitment to stringent training regimes. Pathways now see many players signed to long-term professional contracts while still at school. Some first XV coaches are also thought to be on six-figure salaries.
"If you take all of those factors you can see why there's increased pressure and risk of integrity issues whether that be player eligibility or supplement use. It's a higher risk environment than it's ever been. It's televised, and in some cases seemingly much more important to the big schools than it has been. That's probably part of the reason why DFS has decided to take the position they have now."
Outside teams it is directly responsible for, NZ Rugby provides online interactive programmes which cover supplement polices; DFS offer and run anti-doping workshops. Before now, though, many of these have been overlooked by leading rugby schools.
"It's accessible. As to how the message is received and acted on that's a little bit harder to gauge. The difficulty gauging that is part of the reason why DFS has decided to undertake testing at the top four.
"It's not really a surprise. It's DFS's remit to decide on testing and we support that remit."
Clearly, lack of education around supplements breeds inherent risks. And the big worry around testing teenagers comes with unintentional consequences; the potential of future prospects being ruined by a genuine mistake.
If a player is found guilty of taking a banned substance, they will be subject to a NZ Rugby tribunal assembled in accordance with the World Anti-Doping Agency code, the results of which will then be made public.
"That's a risk but we've got a good relationship with DFS and we trust them to get that right. There's a lot of work to do in the next couple of months for sure but there's no reason why they can't do it. They're well resourced, and if schools embrace this there will be every opportunity to get this sorted."
The other issue raised by schools is one of consent. DFS does not require parental permission because the top four tournament is held under the auspices of NZ Rugby who are signatories to the WADA code.
"It's not really for us to get involved in the consent process. We're dealing with minors so I understand why people would be concerned about that but this is a professional organisation that have tested people under the age of 18 previously in other sports so we back them to get it right."
