Hey i just rode 107 miles today on my mountain bike through philadelphia. The time it took was 9 hours, 42 minutes, and 14 seconds. I dont ride professionally just for fun. I wasnt really tired afterwards, but my shoulders hurt from the 8 pound backpack i was wearing, and my feet hurt cause i was wearing Pumas. Im 17 years old, weigh 160 pounds. Just wondering if I need to improve on anything. Opinions?