BuddyPress.org

You can go into the header.php file in your template and do it in there

<li<?php if ( bp_is_page( BP_MEMBERS_SLUG ) ) : ?> class="selected"<?php endif; ?>><a href="<?php echo get_option('home') ?>/<?php echo BP_MEMBERS_SLUG ?>" title="<?php _e( 'Members', 'buddypress' ) ?>"><?php _e( 'Members', 'buddypress' ) ?></a></li>

You can change _e( 'Members', 'buddypress' ) ?>"><?php _e( 'Members', 'buddypress' )

to _e( 'Analyists', 'buddypress' ) ?>"><?php _e( 'Analysts', 'buddypress' )