Jenkins has remained at home to receive treatment on the injury he sustained while on Heineken Cup duty for Cardiff Blues against Racing Metro.
The Lions front row is the only absentee from the 35-man party that arrived in Gdansk on Monday, but he is expected to be given the all-clear to join his team-mates later in the week.
Fly-half Rhys Priestland (knee) and back row Dan Lydiate (ankle) were substituted during the weekend's European action, but will train in Poland while their injuries are managed.
Centre Jamie Roberts (knee) is recovering well and will continue his rehabilitation in Gdansk, while Lee Byrne (thumb) has been cleared to take a full part in training.
Wales have returned to the facility that served them so well during the build-up to the World Cup, helping produce one of the tournament's fittest teams.
Wales open their RBS 6 Nations campaign against Ireland at Lansdowne Road on Sunday week.