Forum's Slowed to a Crawl

[Elemental Crisis]

Hello,

It seems after trying to send a bulk mail (61 Members) my forums speed has slowed down significantly. I went from load times of .200 to insane times of .700 through 1.300, even sending a PM the load time was 2.102 or something similar. The only things I've done to try and speed up my forums is

ALTER TABLE `ibf_core_item_markers_dev` DROP INDEX `item_member_id` ,

ADD INDEX `item_member_id` ( `item_is_deleted` , `item_member_id` )

and I run this when things get sluggish.

OPTIMIZE TABLE `ibf_core_item_markers_storage`;

OPTIMIZE TABLE `ibf_core_item_markers`;

Though my forums were fine after I did those. Like I said the speeds went downhill when I attempted to send a bulk mail which didn't send and I ended up canceling it. I'm on a shared hosting plan and my options to what I can do to the server is limited but I'll ask my host about any ideas anyone recommends.

Thank you.

EDIT:
Looking at this at the following it seems 3.1.2 will be helping with speed related issues.
http://community.invisionpower.com/tracker/issue-23786-core-item-markers-index-suggestion/