1 day Whitney summit 7/24. Group of three , myself 51 and son 17 from Louisiana, and friend from Utah. Left Lone pine best western at 2 am and started on trail at 2:30 am. Arrived at trail camp a little over 3 hrs at sunrise and replenished water at the pond. 1 liter was plenty for the entire trip due to the abundant water sources. We took 2 liters above trail camp but didn’t need it all. At trail crest there were slippery places to the summit especially in shaded areas due to snow fall the day before. Reached Summit at 8:45 am and spent 45 minutes at summit enjoying the awesome views. Left summit at 9:30 am and reached portal at 2:30 pm. Hiking poles were a must. This was first time using them and they saved my 51 year old knees on descent. No altitude symptoms at all but sleeping at 8,100 ft for 5 days in Park City, Utah condo before hike probably helped. Water proof gortex hiking shoes helped at numerous water crossings along with hiking poles. Pack weighed 12 lbs without water, so keeping weight down helps. Thanks to all posting on this forum for helpful information that helped us plan this hike.