Sembalun is generally considered better than Senaru or Torean for a one-night acclimatisation stop before attempting the Rinjani summit. Here’s why:
* Higher Starting Altitude: Sembalun village sits at around 1,156 metres (3,793 feet) above sea level. Senaru village, on the other hand, is at a significantly lower altitude of around 601 meters (1,972 feet). Torean village is even lower than Senaru.
* Why this matters for acclimatisation: Spending a night at a higher altitude, even just a few hundred meters higher, exposes your body to lower oxygen levels sooner. This situation prompts physiological adaptations that help you acclimatise, such as increased red blood cell production and more efficient oxygen utilisation. Starting your trek from a higher base means you’ve already begun the process of acclimatisation before you even start climbing.
* Faster Altitude Gain on Day 1: When starting from Sembalun, you reach a relatively high altitude campsite (Sembalun Crater Rim, around 2,639 metres or 8,658 feet) on the first day of trekking. This rapid gain at a moderate altitude further accelerates the acclimatisation process. From Senaru, while you eventually reach a similar crater rim altitude, the overall gain on the first day is less. From Torean, you gain altitude very gradually over a long distance, which is less effective for rapid acclimatisation before a summit attempt.
* The “Sleep High, Climb High” Principle: Acclimatisation is often described using the “sleep high, climb high” principle. The altitude at which you sleep is particularly important for triggering the body’s adaptive response. Since Sembalun allows you to sleep at a higher altitude relatively early in the trek, it’s more effective for acclimatisation.
* Less Strenuous First Day: While altitude is key, it’s also beneficial if the first day of acclimatisation isn’t overly strenuous. Although the Sembalun route is long, it features a more gradual ascent in the initial stages when compared to the steep climb from Senaru through the jungle. This means you’re not exerting yourself excessively while trying to adjust to the altitude. The Torean route can be physically demanding due to its length and varied terrain, even if the altitude gain is gradual.
Why Senaru and Torean Are Less Ideal for Just One Acclimatisation Night:
* Lower Starting Altitude: As mentioned, a lower starting altitude means you haven’t started acclimatising significantly before you begin trekking. While Senaru is beautiful, you don’t get the same benefit of pre-exposure to higher altitudes. Torean is similar, though if you spend a significant amount of time in the higher sections of that route (e.g., near Goa Susu) before the summit, there might be some acclimatisation benefit.
* Steeper Initial Climb from Senaru: The steeper climb from Senaru can be harder on your body, especially if you’re not fully acclimatised. This can increase the risk of altitude sickness.
Important Considerations:
* Longer acclimatisation is best: a single night is better than no acclimatisation, but ideally, spending two nights at Sembalun Lawang before trekking would be even more beneficial. This allows your body more time to adapt before the significant altitude gains of the trek.
* Listen to Your Body: Even with a night in Sembalun, it’s crucial to monitor yourself for symptoms of altitude sickness. If you notice any symptoms, please descend immediately.
* Individual Variability: Acclimatisation is a highly individual process. Some people adjust more quickly than others.
* Hydration: Drink plenty of fluids.
* Avoid Alcohol: Avoid alcohol before and during your trek, as it can interfere with acclimatisation.
In Summary:
While any acclimatisation is better than none, Sembalun is a strategically better choice than Senaru or Torean for a one-night pre-trek acclimatisation stop for a summit attempt on Rinjani because it provides a higher starting altitude and a less strenuous (initially) ascent that promotes faster acclimatisation before the major altitude gains. However, always prioritise your safety; listen to your body, and consider a longer acclimatisation period if possible.