Escaping the "World Cup bubble" and developing mental toughness will be as vital as England's on-pitch preparations for this autumn's tournament, says Leicester's Dan Cole.
Cole is likely to be one of the 45 England players heading to a pre-World Cup training camp in Denver next week.
The 27-year-old prop told BBC Sport being away as a group is crucial.
"The mental side is as hard as the physical side because it is a home World Cup," Cole said.
"There will be lots of attention every day. Taking the squad out of the World Cup bubble will help get the bonds between the lads, because the teamwork and camaraderie will probably be what gets you through to the latter stages of the World Cup.
"The ability to manage your down time and get away with the family is important."