显然，尽管监禁多年，他依旧保持着身体健康。用英语怎么说？

显然，尽管监禁多年，他依旧保持着身体健康。

He'd obviously kept himself fit despite his years of confinement.

obviously

adv. 明显地；

例句
I thought he was very attractive and obviously very intelligent...
我觉得他魅力非凡，才智过人。

kept

adj. 受人资助控制的；v. （使）保持， （使）继续（ keep的过去式和过去分词 ），（食品）保持新鲜，保有，保存；

例句
They had given an absolute assurance that it would be kept secret.
他们信誓旦旦地保证将对此绝对保密。

himself

pron. （反身代词）他自己，（用以加强语气）他亲自，他本人；

例句
He pleaded guilty before a court martial to absenting himself without leave.
在军事法庭上他对自己擅离职守表示服罪。

fit

vt.& vi. （使）适合，安装，合身；adj. 合适的，恰当的，合身的，健壮的；n. 合身，适合，匹配，发作；

例句
It's only a theory, admittedly, but the pieces fit together...
诚然，这只是一种理论，但各部分互相吻合。

despite

prep. 尽管，虽然，不由自主；

例句
The gentleman, despite his advanced years, helped Kathryn back to her seat.
这位绅士，尽管年事已高，仍然帮着凯瑟琳回到座位上。

his

pron. (he的所有格)他的，(he的物主代词)他的东西；det. 属于他的，用于名词前，自己的，指某人的，上帝的；

例句
He claimed that his parents had abandoned him...
他声称父母遗弃了他。

years

n. 年( year的名词复数 )，年纪，一年的期间，某年级的学生；

例句
His wife was sentenced to seven years imprisonment for aiding and abetting him...
他的妻子作为他的从犯被判入狱7年。

of

prep. 关于，属于…的，由…制成；aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气]；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

confinement

n. 监禁，关押，分娩，生产，限制，约束；

例句
She had been held in solitary confinement for four months...
她被单独关押了4个月。