In general for LEDs the average current is the important parameter, as the light is generated as the elections move through the device. Each electron that moves through the LED emits a little bit of heat and light, and in doing so will lose around 3.4V of energy.
For this LED you need to design such the the average current is less than 700mA, and the peak current is less than 1A.
A 1A current that is on 70% of the time, and quick enough you can't see it flash is also acceptable.
Any more current than this risks breaking the device.