Let $X=(X)_{0\le t\le 1}$ be a continuous martingale starting at $0$, then denote by $\mu$ and $\nu$ the probability laws of $\int_0^1X_tdt$ and $X_1$. Then it is easy to see that the couple $(\mu,\nu)$ is increasing in convex order, i.e. $$\int_{R}f(x)d\mu(x)~~\le~~\int_{R}f(x)d\nu(x)$$ holds for all convex functions $f:R\to R$ of linear growth, see also "Peacocks and Associated Martingales, with Explicit Constructions" for further details. Now my question is given by probability measures $\mu$ and $\nu$ on $R$, could we give some conditions on the couple $(\mu,\nu)$ such that there exists a continuous martingale $X=(X)_{0\le t\le 1}$ satisfying $$X_1\sim\mu~~\mbox{and}~~ \int_0^1X_tdt\sim\nu$$