Mark Cockroft is an open water swimmer from New Zealand and a member of the Taupo x 3 relay, a three-way crossing of Lake Taupo by a 6-person male team and a 6-person female team of experienced open water swimmers in January 2009. The Taupo x 3 relay teams set a world lake swimming record by completing a 126 km (78.2 miles) triple-crossing of Lake Taupo, the largest lake in New Zealand under organisers Chris Palfrey, Penny Palfrey, and Julie Bradshaw. The swim started at 5:33 am on 5 January 2009.
The men's relay team finished in 33 hours 31 minutes 15 seconds and included Steve Junk (Australia), Mark Cockroft (New Zealand), Dougal Hunt (Australia), Chris Palfrey (Australia), and Stephen Spence (Australia) with New Zealand legend Philip Rush as the escort pilot.
The women’s relay team finished in 33 hours 33 minutes 45 seconds and included Julie Bradshaw (England), Michelle Macy (USA), Barbara Pellick (Australia), Penny Palfrey (Australia), Lucy Roper (England), and Heather Osborn (New Zealand).
• No wetsuits. Swimsuits must be FINA approved. • No artificial aids. • No external assistance to the swimmer. The swimmer cannot be touched (except on the relay changes) or be supported while swimming. • Relay changeovers to occur each hour. That is, one person swims for one hour, and then has five hours rest, repeating the sequence until the finish. • Each relay change to occur by the fresh person swimming up behind the retiring swimmer, tagging hands above the water and then taking over. • Swimmers to remain in their designated order. • Swimmer to clear the water at the end of each lap and immediately return and recommence swimming.
The water temperature was 18.5°C (65°F).
The plan was to start at first light from near Tokaanu, at the southern most point of the lake, heading roughly north east past Motutaiko Island, cutting close to Rangitiri point, before finishing on the beach in front of the Waikato River. The distance by GPS for one lap was 40.2 km. The second lap retraced the course back to the starting point and the final lap was a repeat of the first.
The men finished the first leg of 40.2 km in a time of 10 hours 22 minutes; the women finished in 10 hours 28 minutes.
The men finished the second leg of 40.2 km in 12 hours 15 minutes; the women finished in 12 hours 19 minutes.
The men finished the third leg of 40.2 km in 10 hours 54 minutes; the women finished in 10 hours 53 minutes.
Both teams broke the world relay record set in December 2008 by 2 teams of 50 swimmers, each doing 2 km, who covered 100 km in 37 hours 6 minutes.