Warning: Undefined array key "visitor_referer_type" in /var/www/vhosts/wordinf.com/core/app/libraries/Core.php on line 98 Don Kardong - Train at the same pace day after day,...
Train at the same pace day after day, week after week, year after year, and that's the kind of running the body adapts to. But break out of that comfort zone with a little speedwork now and then, and the body will learn to deal with the new demands.