Well I know I'm not the only one who noticed, but I might be the only one here who knows it.
The lightning around the rival was red whenever he used the speed force.
Now in the comics the red lightning, the negative speed force was used by Professor Zoom.
Here are some facts:
Negative Speed Force Powers
The following powers are exclusive to Professor Zoom, a user of the Negative Speed Force.
Speed Force Negation: Professor Zoom can apparently shut off speedsters connection to Speed Force by "contaminating" it with the negative energy he generates. He can also remove aspects of their powers, such as their protective aura, causing them to burst into flames.
Memory Absorption: Professor Zoom is capable of using his negative electrical energy to absorb the memories of another person. This process will also rapidly age a person to their death.
Metamorphosis: Professor Zoom is capable of altering his own age at will, such as transforming into a young boy or an elderly man.
By letting the rival have red lightning the show runners seem to indicate that in the show it has no meaning at all other than to indicate that the person using it is an enemy of the Flash.
Which is kind of disappointing because I would've loved if the show explored more aspects of the speed force. Especially that why some speedsters have yellow and others red or blue electricity around them when running or using the speed force. They kind of touched on something interesting when last season they discovered that Zoom has blue lightning because he is faster than Barry and used a Velocity "drug" as well.
Also here on the show they never explained how Eobard Thawne/Reverse Flash got his powers.