Changing foods periodically helps to ensure that no dietary deficiencies or excesses build up over time.

按期调换狗粮能够确保避免过久地饮食不平衡或者适量。

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He or she will likely start by testing your child for nutritional deficiencies, then draw up and supervise a plan for addressing them, usually with a mix of dietary changes and supplements.

他或她可能会先测试你孩子有哪种营养不足，然后制订适合孩子的饮食计划并监督实施，通常是一系列的饮食结构调整和补充。

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Assuming that you are training smart, i.e. with a steady pattern, regular rest and good biomechanics, then dietary deficiencies may be involved.

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