Resizing LVM

I want to resize my lvm /dev/glab/sabertooth from 50M to 70M. The vg have enough space for my to resize it. I've read that you can use lvmextend and resize2fs for ext4, but it involve additional steps. I was able to resize it using the single command below. LVM using
lvmresize -r -L +20M /dev/glab/sabertooth.