Another way to power sensitive analog circuits is by use of an LDO.
Note that, as a strictly general advice, this is misleading while widely seen.
You need a very specific kind of linear regulator which specifies decent PSRR to very high frequencies, some to tens of MHz. Not just any linear regulator.
And not necessarily an LDO. A normal drop out linear regulator is an option as well, depending on what power rails you have available.
Just a bog-standard linear regulator you are likely to choose if you don't know better, passes high-frequency components almost straight through.
Even with those high-frequency PSRR linear regs, you likely need some additional filtering for even higher frequencies (say, >10MHz), so it's not either-or. But this is easily done using ferrite bead as L, which is lossy to prevent ringing (oscillation), just make sure the ferrite bead does not saturate, so this applies to very low-power circuits only, but ADC power often is such.
Also using lossy C (say, tantalum) in parallel with the much smaller ceramic C provides damping for the filter.
Then, the tasks are shared so that the small (typically ferrite bead based) LC takes care of noise above around 10MHz or so, and the (correct type of) linear regulator below about 10MHz (which would require large passives).
Also note that "LDO" is nowadays very widely being used synonymous to "linear regulator", but this is very wrong, it's a specific type of linear regulator with low dropout. Whenever you don't need low dropout, look at all linear regulators to get more choice and not to arbitrarily limit what is available.
Things are getting easier and easier all the time; I'm thinking about a modern ADC which takes so little current that it has allowed the ADC designers to combine power and reference without causing power-related current draw drifts; also allowing powering up the whole ADC from a typical voltage reference rated at say 20mA; also making it possible to use very small ferrite beads to filter without saturating, and so on. As technology goes forward, integration goes up, and modern ICs are easier to use than ever.
Finally, I'm sure you know this, but local bypass cap right at the amplifier power pins offers the final and maybe the most important filter.