What Really Happens When You Miss Training: A Week-by-Week Breakdown

I missed some runs while in Vegas.
Mostly because our days were intentionally vastly unplanned and I chose sleep or the pool, which, esp when on vacation and catching up with a good friend... is totally fine.
But as runners, we tend to lean a bit more Type A than most crowds. Which means it can REALLY crush our souls when we get off schedule or have to miss training (whether it's a vacation, illness, work deadline, weather, etc). And it's not the fear of "can I get back into a routine", that's already mapped out... but how much do I lose when I miss training?
So let's go over it:

• Days 0–2: Basically no loss. Muscles are still glycogen-loaded (sugar sugar baby), and a short break can even aid recovery.
• Days 3–5: Blood plasma volume starts dropping (5–10%), so easy efforts start to feel a bit harder. That "shaking off the rust" feeling. Heat training (thanks, Vegas can help with this as well)
• 1–2 weeks: Aerobic fitness (VO2max) begins to decline — typically 4–6% in the first 7-10 days off.
• 2–4 weeks: Now things really start to shift, mitochondrial capacity can drop 25%+, lactate threshold slips, and VO2max can be down 10-15%.
• Strength, tendons, and bone density: Hold up much longer than cardio fitness. We don't want to neglect them, but if you're tight on time/energy/attention... focus on your runs (for a month or so)
• 4+ weeks: The rate of loss slows, but extended time off brings fitness closer to baseline. Good news: it comes back faster the second time around.​

And now an exercise form tip.
If you have any suggestions, please let me know!
​
When doing a bridge, the goal isn't just to lift your hips as high as possible. Instead, while flat, lock your rib cage down while squeezing your abs. Then, as you lift your hips, focus just on how much you can squeeze your glutes. You won't get as high, but you'll get more out of the exercise.