Single cycle readings defeat the point of sigma delta ADC setups.
You're taking many high noise samples and averaging them over time to get a better picture of the average voltage.
The ADC's internal delta-sigma ADC takes a lot of samples at a much higher modulation frequency and presents them as a single output value.
You do not get the direct delta-sigma output from an ADC like this. The internal logic handles that for you. It's okay to take single samples of the output.
Natively/internally, it runs at 860 samples per second, and you can configure it to provide that data at a lower sample rate at lower noise levels by averaging multiple readings together internally.