It mean increasing the amount of distributor inventory for a given product, which has the effect of boosting sales during the current reporting period at the expense of lowering sales during subsequent periods (because distributors can satisfy more end-user demand from their own inventory).
Channel destocking is the reverse process—it lowers current sales but tends to increase sales in future reporting periods.
“The efficient-market hypothesis may be the foremost piece of B.S. ever promulgated in any area of human knowledge!”