Stop watching 20-year-old documentaries on ESPN Classic, and start reading up on the facts. The 1930 census of Forest City, Arkansas, was revealed a few years ago, and it lists his parents and a few of his siblings, but not Charles. At most, he was 31 years old when he fought Muhammad Ali. The arrest records and anecdotal accounts that list him as being born in 1927 or 1928 - including his mother's own word - are simply wrong.
31 years old. How was he not at his best? He absolutely destroyed Floyd Patterson only seven months earlier, and hadn't shown one bit of deterioration. More to the point, he showed no signs of being past his best until half a decade later when Leotis Martin knocked him out.