The year-on-year percentage increase is a comparison between the last seven days in 2020, and the same week in 2019.
The premium cycling and multisport retailer, which has a store in Hampton Wick as well as a hefty online presence, has grown in the last 12-months but the sales pattern is still "unprecedented" according to managing director Ian Whittingham.
The year-on-year increase when customers from France, Germany, Ireland, Luxembourg, Cyprus and Spain are included stands at 846 per cent.
The rise in the purchase of online trainers is of course a response to the coronavirus pandemic.
Whilst in the UK the government has not banned cycling outside as society works to halt the spread of the virus and reduce the strain on the NHS, there are differing opinions on what activity is advisable at this time.
British Cycling has told the government to officially recommend cycling to the public during the coronavirus outbreak, as a form of maintaining physical and mental health - but it remains to be seen if the advice will be accepted, and elsewhere in Spain riders have reported €3000 fines for those who flout the ban.
Sigma say the number of orders placed has increased by 440 per cent, week-on-week. In addition, it says the launch of the new Wahoo Kickr Indoor Smart Bike and Trainer (priced at £2999.99) which has been available for pre-order from March 19, has seen huge interest with initial drops selling out on pre-order in just a few hours.
Commenting on the pattern, Whittingham said: “In terms of unit volume, over this last week, we have seen that turbo trainers are overtaking bike sales, which is unprecedented.
"We are working closely with our suppliers to replenish and offer more stock to support changing cycling habits in these challenging times.”
He added that the business was following the government and World Health Organisation's advice extremely closely, saying: "Our continued focus on delivering an exceptional level of service while being responsible for our actions is driving us forward and we are committed to catering for our customers' needs while paying a close eye on the bigger, global situation."
The Hampton Wick store and international dispatch centre are both "fully operational" but operating "with stringent measures put in place to ensure all customers and staff are able to visit and work in a safe environment,” he said.
The store organises regular rides, runs and in-store events, and these have all been cancelled. He said: "We are looking to initiate other ways to keep our community active, motivated and healthy, such as by looking to organise virtual rides and classes. It’s very important to keep our community connected and sports are not only a great way to stay physically fit, but also mentally.”
Sigma Sports is not the only retailer reporting a huge uptick in the sale of indoor cycling and exercise equipment.
Decathlon UK says it has seen a "four digit growth on turbo trainer sales," though it also said that there had been an increase in customers visiting the workshop to get old bikes ready to ride, or getting new bikes, as they look for alternative methods of commuting.
Road Cycling Sport Leader at Decathlon, Michael McHale told us: "It's clear that people are looking for alternative methods to travel during this crisis as we have seen a large growth in customers investing in new bikes or servicing their current ones. The main growth has come in trainer sales though and across the whole range. Whether it's the regular virtual riders looking to improve their current setup or someone looking for a basic setup to keep active and engaged during this period of social distancing.
"We are continuing to take measures to ensure that we can safely keep our stores and workshops open and stocked as long as possible to continue providing this."
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