まくる

まくる after a verb means doing it over and over, or flat out, with no let-up: "like crazy", "non-stop". It goes on the ます-stem, and the result conjugates as a godan verb: まくった, まくっている, まくらない.

The stem, not the dictionary form: ×食べるまくる → 食べまくる.

A streak, good or bad

まくる is about excess, so it fits a run of wins as well as a run of losses or a fit of crying.

まくる or 続ける

きごう〜つづける続ける says only that an action goes on without stopping. まくる adds force and quantity: lots of it, with abandon.

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まくる is slang-flavoured and belongs to casual talk, blogs and social media. In polite or written Japanese, use たくさん or なんど何度も with the plain verb instead.