。
Let's face the new recruit training camp in peak condition, both mentally and physically.
Literal
Mind-body together-[with-に] best [genitive-の] condition [with-で] new-recruit training camp [to-に] let's-face.
A motivational call to action. 心身共に (しんしんともに, 'both mind and body') is a formal compound: 心 (mind) + 身 (body) + 共に (together). ベストのコンディション mixes Japanese with loanwords — characteristic of sports and training contexts. 新人養成合宿 ('new recruit training camp') is a four-part compound: 新人 (new person) + 養成 (training) + 合宿 (live-in camp). 臨む (のぞむ, 'to face / to confront / to attend') is a formal verb for approaching a challenge. ~ましょう is the polite volitional.