Longer cardio or shorter, multiple sessions?

jack3514

Most of my exercise routine is cardio on a Nautilus stationary bike. I've gone from no exercise to to build up to 60 minutes in a single nightly session, six days a week. The intensity levels vary in a "rolling hill" scenario where, after ~10 minutes of warming up, my heart rate ranges between 70% to 85% of the maximum heart rate for my age. (See http://www.mayoclinic.org/healthy-lifestyle/fitness/in-depth/exercise-intensity/art-20046887?pg=2)

I'd like to incrementally increase my exercise, but can't really increase the intensity much. I'm looking at adding some more minutes to my routine. I'm not sure if I should add more time to the single session where all of the extra time is at the elevated heart rate, or split the cardio into two sessions, either evenly or a shorter session in the morning and a longer in the evening.

My concern about splitting sessions is that a higher percentage of the total exercise time will be warming up at the lower heart rates. Honestly, I can't say I really enjoy exercising that much - and enjoy it even less at the beginning of the session! Knowing I'm spending ~25% of my exercise time warming up with no real cardio benefit (i.e. calorie burn) seems a real disincentive. But maybe two sessions will be better to raise my metabolism throughout more of my day so the total effective calorie burn will be higher?

I'd like to hear your thoughts about whether I should lengthen a cardio session or split it into two?

Bonus question: Does time of day matter for the cardio? I do it in the evening because I can control that schedule better. Would early morning before work be better than early evening after work?

PS. While exercise is not a fun thing for me, I will say the evening sessions really help me sleep well!

Thanks in advance.

janejellyroll

I can't speak as to the specific impact of splitting sessions (although sometimes I will do two cardio sessions in a day), but I will say that some studies have shown that exercising in the AM does have some advantages over exercising in the PM. But exercising in the PM is much, much better than skipping it if the PM really works better for you. The PM workout you do is better than the AM workout you meant to do but skipped due to scheduling conflicts or hitting the snooze button. And that it helps you sleep better is a bonus!

vespiquenn

This depends on what you goals are. Are you cycling because you enjoy it and are just using it to lose weight? If so, then the calories in, calories out is all that matters. Raising your metabolism does not happen in terms that you are describing. So it does not matter if you do a short time or long in regards to burning calories.

However, if your goal is to build endurance, then short distances will eventually have a cap on improving endurance. Short distances have their place, but they should be alongside longer distances. For example, I am training to become a better runner. Some days I run a short distance but practice speed work. One day a week, I run my long run, which is at a slower, steadier pace. So it boils down to what you are hoping to achieve.

Also, time of day for your workout does not matter unless you find issues with sleeping at night. I typically do cardio in the morning and weightlifting at night because my body is not awake enough to lift in the morning. As long as you're getting it done, it doesn't matter.

NorthCascades

jack3514 wrote: »

Knowing I'm spending ~25% of my exercise time warming up with no real cardio benefit (i.e. calorie burn) seems a real disincentive.

You'll have a real benefit in that you're improving your cardiovascular fitness.

You should seriously consider reducing the intensity of your exercise. For optimal cardio health you should exercise at a variety of intensities, but generally most of your time should be spent at a more moderate level. Athletes tend to spend 80 % of their training sessions at moderate intensity and the other 20 % at a very high intensity. There's a saying that most people go too hard on their easy days and too easy on their hard days. Mind you their goal is to compete, not to lose weight. As for weight loss, most people experience more hunger after intense cardio exercise than after much longer moderate cardio, because intensity burns glucose which is much more limited and important than fat, so your body demands you eat (mostly carbs) to replenish it. Runners know this as "runger."

jack3514

NorthCascades, The "rolling hills" scenario I use varies the intensity over a 20 minute cycle and I typically do three cycles. The highest intensity is only 10% of that cycle. I love peanuts, but can't have many. I usually have 1 oz of peanuts after my workout. Not only are they a nice reward to look forward to, but they kill off any cravings I might have had for worse snacks and are relatively high in protein. I take the small calorie hit, but it seems to be worth it.

Cherimoose

From a health perspective, it's better to spread exercise throughout the day, if the rest of your day is mostly sedentary. Split sessions shouldn't give much of a reduction in calories burned, but if it does, simply eat less. Fat loss should really come from controlling calorie intake, not from modifying one's fitness regimen. Speaking of which, are you doing strength training too (full body)? Cyclists who don't tend to have lower bone density, according to studies.

alanlmarshall

Look into HIIT.