Triathlon is mainly non-ticketed and hundreds of thousands of people are expected to line the route to cheer on the athletes.
Jenkins said: 'It's unbelievable to see how many people have been supporting... A lot of the athletes say that support really pushed them on so obviously I'm hoping that happens for me.'
Other medal contenders include Australia's Erin Densham and Nicola Spirig of Switzerland, who have won two World Series races each this season.
New Zealand's Andrea Hewitt and Lisa Norden of Sweden are also expected to challenge.
The Olympics is so exciting and as an athlete it's something that you've thought about, dreamt about and worked towards for such a long time, you want to enjoy every minute of it.Helen Jenkins
The 27-year-old Jenkins goes into the race as the reigning world champion and a dominant winner of the test event in Hyde Park 12 months ago.
This season she also bagged a second place in the World Triathlon Series race in Sydney and then a victory in San Diego she rates as her best race.
That was in May and Jenkins has been training hard since, latterly with team-mates Vicky Holland and Lucy Hall, who will help her in her bid for Olympic glory.
The wild card in the Triathlon is Canada's Paula Findlay, who burst onto the scene in Hyde Park two years ago with a stunning victory and promptly won four more races, but she has struggled with injury for the past year.
Jenkins added: 'We just don't know where Paula is. Although a lot of people are not considering her, I'd say she's probably one of the favourites.'
Meanwhile, Aileen Morrison will hope to mount a medal challenge for Ireland after finishing second at the World Series race in Madrid in May.
The British trio are staying near Hyde Park rather than in the Olympic Village. Jenkins said: 'It's pretty calm and I'm enjoying that, it's not too hyped up.
'The Olympics is so exciting and as an athlete it's something that you've thought about, dreamt about and worked towards for such a long time, you want to enjoy every minute of it.
'It is easy to get carried away but for us the focus is very much the race and we can enjoy the whole Olympic experience after that.'