Originally Posted by wikek
Hi!
I need to loose a few kilos and I'm wondering how best to do it. Does losing weight affect training of vo2max, threshold or any other properties? In other words, should I lose weight first and start improving my absolute values when I'm at the weight I want to be?
Since VO2max is a function of weight, all things remaining equal loosing weight will increase your VO2max. It may or may not affect the "training" of VO2max. Just make sure you are eating enough to maintain enough blood sugar during your workouts. Start training and weight will likely be lost as a result so long as you don't go overboard eating after rides. On the flipside, if you increase your endurance and your weight remains the same, your VO2max may see an increase as well.
It depends upon the training however. Unless you are completely sedentary tooling around in Z1/2 won't do diddly for you VO2max. You will need to exert the appropriate intensity... at least 80%+ of you maxHR, preferably 90%+. And if using a power meter, a typical VO2 intensity workout is 105-115% of your FTP measured in a field test. I.e if you want to train VO2, you need to spend time at or near VO2. Training FTP or endurance are separate topics.
It's ok to have a calorie deficit while building power (and increasing VO2), just make sure to have fuel for your workout, some carbs immediately after to help replenish glycogen stores, along with enough protein to insure muscle repair (3-4x a day). Some protein to start the day. Some protein during lunch, and with dinner is fine. One thing I like to include between meals when cutting weight during a "build cycle", is Chobani greek yogurt, super high in protein (12g) considering it's a small low cal serving. Since the body can only take in a certain amount of protein at a meal anyway, largely dependent on existing muscle mass, there's no need to go overboard... 15-20 grams is plenty, the rest will just get peed out. It's entirely possible to increase both power levels and get closer to your genetic VO2 ceiling without increasing muscle mass though. Luckily cycling is not bodybuilding (which I have also done), and while conventional wisdom dictates bodybuilder's need to maintain a calorie surplus, one of Franco Columbo's strategies (ever hear of him? He's twice winner of Mr Olympia) was to cut weight prior to a build, practically unheard of in bodybuilding circles.
As for W/kg, while having a lower body weight at the same power output your value will be higher, and it may "ballpark" your potential, but it is not necessarily a marker for performance.
When I got back into racing a few years ago, training helped me cut the weight (185 to 160lbs over the course of about 5 months without dieting). Last year I took some time off the bike and I didn't do too much serious riding but I started cutting calories in November (Thanksgiving was an exercise in pure willpower!) and by the end of December when I started training again I had already dropped 10lbs (165 to 155lb). Now I just make sure to eat enough to maintain energy during workouts and check myself on the scale every few days to make sure I'm not going too far off base on the consumption. The benefit is that with racing only one month away, I am already at my target weight (now at 150lbs), and getting stronger on the bike each week.
Hopefully some of this helps.