On your first day, or first and second days, of the Alpine crossing, from Lake Geneva (Lac Léman), you will need to ascend 4,000 – 5,000 feet (1,300 – 1,700 meters). Obviously, you will need to be in pretty good shape before you leave.
Fitness is sport specific, so, if possible, prepare yourself by hiking in mountains near home. When I couldn’t get to the mountains, a very steep 400 foot high hill served for conditioning, by climbing rapidly up and down it 3 or more times.
If your only recourse is fitness machines, then the following exercises should also prepare you: 1) Walk on treadmills set on a 20% slope at 2 miles an hour or more; 2) On a stair-climbing machine with actual steps (where you have to lift your feet to the next step), climb 100 flights, ideally within 40 minutes or less and without undue fatique; 3) strengthen your quadriceps (utilized mainly in going downhill) on a machine designed for this propose.
Be forewarned: I personally know of two examples of middle-aged men who thought they were fit, because they worked out in the gym. They also thought that because certain women they knew could do the GR5, it would be no problem. In both cases —though they were told they should— they did not do the specific exercises recommended above or practice hike. In both cases they were physical exhausted on the GR5 after their first two days of hiking (which required thousands of feet of vertical elevation), and they had to abort their trips (in one case bad weather was a major contributing factor).
American and English hikers may be disconserted to find that in the Topo-Gides and other guide books time, rather than distance, is used as the measurement between two landmarks. For example, the Topo-Guides don’t tell the distance from the shores of Lake Geneva to the village of Novel, but rather give a time: 2 hours.
The author has come to find this time system quite reasonable for measuring Alpine hiking. Most of the Alpine trails are much steeper than most trails in the American West (but not steeper than trails in the Appalachians), and one’s speed (and effort) are not directly related to distance between two points. One’s effort is more closely related to time spent. Additionally, the use of time makes it easy to calculate where you might have lunch, where you can reach in a day
In certain cases, such as valley walks, or long assents or descents at minor grades, you will want to know the mileage, which can give a good indication of wear and tear on your body. Calculate the mileage from the times in the book, or from maps.
After a few days of warm-up walking, you will be able to compare your speeds with those listed in the guide books. In my experience, it can be difficult to function at top speed the first day or two. The Topo Guides use approximately 300 meters (1000 feet) per hour up very steep slopes, about 400 to 600 meters (1,400 to 2,000 feet) per hour going down, and about 4 km (2.4 miles) per hour on the flat. ( The guides are usually, but not entirely accurate or consistent.) The Paddy Dillon guidebook uses about 400 meters (1,400 feet) per hour up and down on steep slopes. Compare your time with the book time as you climb, descend, and walk on the flat. Remember that guidebook times do not make an allowance for rest stops or meals.
Schedule a rest day at least once a week, if for no other reason than to allow your body and spirit to recover. Some suggestions for rest day locations are made in the route pages of this site.