Single errorbar on a constant line

Hello, I have been doing some calculations on muscle signals. I have time:

    time = [0:50000:10] %

Sampled for 10 sec, 5000 Hz. And my data is 50000 corresponding mV values. I've taken the absolute of that and mean of mean within three muscle contractions, which ends up with one single value (I need an average muscle amplitude to active a vibrator). Anyway, I've tried numerous errorbar-configurations. Both the above time, and:

    y = mean(mean(data)) .* ones(size(time)) % y for errorbar
    e = std(data) .* ones(size(time)) % e for errorbar

The above ended up looking like a big square box, because of all those errorbars clustered together. I have also tried doing the errorbar calculation for one single y value and x value, however, that is not really representive of what I want to show because that just ends up being a single point with errorbars, which doesn't show my constant line over time.