Increasing the sample rate or bit rate will not improve the quality of an existing recording. If the sample rate or bit rate is low on a recording, information has already been lost which cannot be recovered.
For example, if you are working with an 11-Khz WAV file, increasing the sample rate of the file will only improve new effects added to the file.
The sample rate tells you how many samples per second are recorded.
High sample rates (e.g. 44.100 Hz) produce higher-quality results than low sample rates (e.g. 11.025 Hz), but they also make your audio files larger.