Hi,
Apparently meditation and deep relaxation is upposed to be the exact counterpart of sress, tension and frustration, thus the best way to release all that pent up emotion. It is hard to believe that all of that can be released without 'physical' activity.
Spend some time being quiet with yourself and ask your body what it needs to release stress and tension. Or perhaps ask your body what creates tension and stress in the first place and then try to eliminate those instigators as much as possible.
Lastly, and this is probably the most effective and simple, is to breathe deeply. Shallow breathing is what we human are used to, whereas very deep breathing opens us up and relaxes us as we progress through the day, probably not allowing the stress to build up in the first place.
Another option could be EFT (emotional freedom technique), which works with the energy points on your body to release blockages. Again, a very simple technique, once understood and memorized, free and you can take it everywhere! For more info, type emofree.com or something like that.
Try, experiment and see what works and what doesn't. it is your body and the answers you seek already exist within you and are most certainly accessable.
Good luck