Despite of what I wrote about using water bottles for dumbells, I do have access to a nice little real fitness-room at the place where I work. There also is a cycle-trainer there and as I can't ride my bicycle in the snowy weather we have now, I am happy to have at least that. There are some anvantages too (though I prefer real cycling when I have the option) - it shows the pulse, calories, power in watt, speed, time, and more. And there are 15 levels.

I calculated my ideal training pulse withthe help of a formular and try to go 20 minutes at that pulse. If I do that at level 10 I get the best results in watts and calories. If I use, say, level 6, I have to go very fast to get my pulse up, and still the watts and calories are less than at level 10. Or I go even faster to get the same watts, and then my pulse gets higher and I won't do that for 20 minutes surely.

At level 14 or so I hardly can move the pedals at all but if I do, the pulse also gets high faster that the watts do.

So what is best for keeping my cardiovascular system fit? to train always at level 10 where I get the best result, or to use other levels too?

Some time ago I was riding old bicycle when the chain broke. I managed to roll 10 kilometres (150 metres down) on a former railroad trail so I got almost to my point of destination without having to get off and push. But it was very slow. I think the weight of my bag helped me. There were tools in it (unfortunately, none to repair a chain) but also 1,5 litres of water and some apples and sandwiches. I was afraid to comsume any during the rolling part not only because I was unwilling to stop the mostion but also because I thought it might reduce the weight. Would it? There was no toilet on the way, so the question is: wuold my body have breathed out more CO2 and breathed and sweated out more water if it had got more? I was not critically hungry or thirsty at that time, just a bit.

I have recently been living in Guyana's rainforest, and have consumed a large number of magoes. Now, I always assumed that a ripe mango would contain more calories than a green one. They certainly taste a lot sweeter. Is this actually the case? And i so, how does the mago aquire this additional energy if they are picked whilst still green and allowed to ripen afterwards?

I.e. if I eat complex carbohydrates to the value of 1000 calories, are these just as likely to increase my body fat as by eating fat or sugar to the value of 1000 calories?

Does the fact of thinking, of having an intense cerebral activity, lead to more burning of calories? When one has a prolonged mental activity, especially involving concentration, one usually becomes tired and/or hungry... Does this mean that thinking is good "sport"? Is it coherent to imagine a small, non-sporty but intensively reasoning person needing and consuming as much calories as a stronger sportperson?

I am aware of general advice that the average male needs 2500 calories a day, but this will include energy expended during a day's activities. I also recognise that the calories used are dependant on the weight of an individual. Is there a formula that represents the calorific requirement to stay alive of an individual at complete rest, reflecting that individual's weight? If so, at 14 stone, what would be my necessary calorific intake to stay alive if I remained in bed all day?

Easy enough for runners or other load bearing exercises.  But in swimming (and I suppose other activities) there are many variables.  Is it possible to come up with a meaningful average given:

• the mass of the swimmer
• the speed of the swimmer; and
• the resistance of the water, which will vary depending on

1. how much of the swimming stroke is out of the water and in the air (arm recovery and also stroke dependent, i.e breaststroke, butterfly, etc);
2. the streamlining efficiency of the swimmer, which will affect the resistance of the water
3. how long a swimmer can maintain a given efficiency (tiredness during the hour will impair the ability to stay efficient)
4. the temperature of the water

If a person does exactly the same sorts of activities in the summer when it is warm and in the winter when it is cold, do they use more callories in the winter in order to keep warm?