How many hours a week should I excersise

TIme is not really the measure of effectiveness, though it's part of the equation.

IMO, the most important thing is to settle into a routine that has you spending an amount of time on exercise that fits into your life well, with good overall life balance. By 'good overall life balance', I mean enough time and energy for job, family, home chores, social life, non-exercise hobbies, and generally anything else that's important to you personally.

There's no one perfect time allocation, and there are a lot of variables. (Example: For some, a good fraction of social life happens at the gym. For others, all socializing happens elsewhere, and workouts are non-social.)

If you have specific athletic or fitness goals, that matters, too. Even then, a hour spent on good training is potentially more valuable than 3 hours spent noodling around with a poor training plan.

For your stated goals, which are frankly still a little sketchy ("want to lose 5 kilos and then gain 3 of just muscle"), the fat loss part is about calorie balance (eating less than you burn from daily living + exercise), though both strength and cardio can let you eat a bit more (and be healthier) while losing at the same rate, vs. just reducing calorie intake to get the same loss rate.

For muscle gain and muscle retention while losing fat, the most important variables are choosing a well-designed plan and following it consistently, while getting good nutrition (especially protein) and avoiding ultra-fast weight loss. (With only 5 kilos to lose, you probably won't be best served by losing at a fast rate anyway.) There's a list of good programs here:

http://community.myfitnesspal.com/en/discussion/10332083/which-lifting-program-is-the-best-for-you/p1

Different programs have different time requirements and objectives, but the amount of time you're spending per week now ought to be able to get you some decent progress, if the time is well spent. (You can ask questions about the programs on that thread.)

If you're still relatively new to strength training, and losing slowly, you might even possibly see some slow muscle gain alongside fat loss, especially if you're relatively young.

As far as cardio, unless you have specific athletic or performance objectives, that's just about getting your heart rate up a bit, and burning some calories to increase the food budget. If your main goals are about muscularity, I'd suggest not going for high intensity cardio (especially at first) or cardio that has a strength component, as those are more likely to compromise your strength training recovery. (Recovery is where the gains happen.) There are a huge range of options, but some good choices could be easy cycling, swimming, walking, running, dancing of various sorts: Not fatiguing, not majorly strength-taxing.

As you get fitter, you can begin to work in some higher intensity cardio, but still as more of a condiment or side dish in the overall exercise menu, not as your daily routine. (I'd observe that what counts as "intense" will change, as you get fitter, however. If you run, for example, your "easy run" pace will gradually get faster, because that's what fitness development is. Also, if you run half an hour a day, just as an example, that gradually increasing speed will burn more calories in the 30 minutes, while continuing the slight challenge that keeps fitness progress happening.)

In general, the smartness in the time you spend is a more crucial factor than the length of time you spend, across quite a range of values of time. If the hour a day, most of 5 days, is working well for you and you're enjoying what you're doing, you should be able to achieve lots with that time commitment.

I don't know what your sister's program is, but wouldn't it be fun if you could get *better* results while spending *less* time? 😉

Best wishes for good progress!

What are your specific fitness goals?
(I've only seen weight loss and muscle gain goals plus sibling rivalry.)

It's sounding that beating your sister is the primary driver!
But beat her how?
Run faster or further?
Lift heavier?
Or just beat her up in a fight perhaps?!

Without knowing what goals you are training towards it's hard to judge whether 5hrs a week is sufficient.
If your vision of "really fit" is running a marathon or cycling a century then very clearly 5 x 30mins of unspecified cardio isn't adequate. What does "really fit" mean to you?

More is not always better. If I exercise for an hour and then feel capable of doing another hour I've not been working hard enough in the first hour. (Clearly if you are training for endurance activities such as marathons then you have to train at a level that permits you to spend longer, but for general everyday fitness improvements I find an hour a day is just fine.)

sakurablossoms82 wrote: »

In The Netherlanders there is this minimum guideline for adults:
150 minutes per week low to high impact exercise.
Minimum of 2 times a week of strength/endurance training to get stronger muscle and bones.
For elderly that also includes exercise to improve balance such as yoga.

Very similar to the Health Canada guidelines.

AnnPT77 wrote: »

BrianSharpe wrote: »

sakurablossoms82 wrote: »

In The Netherlanders there is this minimum guideline for adults:
150 minutes per week low to high impact exercise.
Minimum of 2 times a week of strength/endurance training to get stronger muscle and bones.
For elderly that also includes exercise to improve balance such as yoga.

Very similar to the Health Canada guidelines.

And to US HHS guidelines.

snip

Almost as if these national bodies talk to one another, and rely on the same research, eh? 😉

I suspect that's because this all appears to emanate from the WHO. :-)