**Highlights**
1. Support ["Lite-HRNet: A Lightweight High-Resolution Network"](https://arxiv.org/abs/2104.06403) CVPR'2021 ([\#733](https://github.com/open-mmlab/mmpose/pull/733),[\#800](https://github.com/open-mmlab/mmpose/pull/800)) jin-s13
2. Add 3d body mesh demo ([\771](https://github.com/open-mmlab/mmpose/pull/771)) zengwang430521
3. Add Chinese documentation ([\787](https://github.com/open-mmlab/mmpose/pull/787), [\#798](https://github.com/open-mmlab/mmpose/pull/798), [\#799](https://github.com/open-mmlab/mmpose/pull/799), [\#802](https://github.com/open-mmlab/mmpose/pull/802), [\#804](https://github.com/open-mmlab/mmpose/pull/804), [\#805](https://github.com/open-mmlab/mmpose/pull/805), [\#815](https://github.com/open-mmlab/mmpose/pull/815), [\#816](https://github.com/open-mmlab/mmpose/pull/816), [\#817](https://github.com/open-mmlab/mmpose/pull/817), [\#819](https://github.com/open-mmlab/mmpose/pull/819), [\#839](https://github.com/open-mmlab/mmpose/pull/839)) ly015, luminxu, jin-s13, liqikai9, zengwang430521
4. Add Colab Tutorial ([\834](https://github.com/open-mmlab/mmpose/pull/834)) ly015
**New Features**
- Support ["Lite-HRNet: A Lightweight High-Resolution Network"](https://arxiv.org/abs/2104.06403) CVPR'2021 ([\#733](https://github.com/open-mmlab/mmpose/pull/733),[\#800](https://github.com/open-mmlab/mmpose/pull/800)) jin-s13
- Add 3d body mesh demo ([\771](https://github.com/open-mmlab/mmpose/pull/771)) zengwang430521
- Add Chinese documentation ([\787](https://github.com/open-mmlab/mmpose/pull/787), [\#798](https://github.com/open-mmlab/mmpose/pull/798), [\#799](https://github.com/open-mmlab/mmpose/pull/799), [\#802](https://github.com/open-mmlab/mmpose/pull/802), [\#804](https://github.com/open-mmlab/mmpose/pull/804), [\#805](https://github.com/open-mmlab/mmpose/pull/805), [\#815](https://github.com/open-mmlab/mmpose/pull/815), [\#816](https://github.com/open-mmlab/mmpose/pull/816), [\#817](https://github.com/open-mmlab/mmpose/pull/817), [\#819](https://github.com/open-mmlab/mmpose/pull/819), [\#839](https://github.com/open-mmlab/mmpose/pull/839)) ly015, luminxu, jin-s13, liqikai9, zengwang430521
- Add Colab Tutorial ([\834](https://github.com/open-mmlab/mmpose/pull/834)) ly015
- Support training for InterHand v1.0 dataset ([\761](https://github.com/open-mmlab/mmpose/pull/761)) zengwang430521
**Bug Fixes**
- Fix mpii pckh0.1 index ([\773](https://github.com/open-mmlab/mmpose/pull/773)) jin-s13
- Fix multi-node distributed test ([\818](https://github.com/open-mmlab/mmpose/pull/818)) ly015
- Fix docstring and init_weights error of ShuffleNetV1 ([\814](https://github.com/open-mmlab/mmpose/pull/814)) Junjun2016
- Fix imshow_bbox error when input bboxes is empty ([\796](https://github.com/open-mmlab/mmpose/pull/796)) ly015
- Fix model zoo doc generation ([\778](https://github.com/open-mmlab/mmpose/pull/778)) ly015
- Fix typo ([\767](https://github.com/open-mmlab/mmpose/pull/767)), ([\#780](https://github.com/open-mmlab/mmpose/pull/780), [\#782](https://github.com/open-mmlab/mmpose/pull/782)) ly015, jin-s13
**Breaking Changes**
- Use MMCV EvalHook ([\686](https://github.com/open-mmlab/mmpose/pull/686)) ly015
**Improvements**
- Add pytest.ini and fix docstring ([\812](https://github.com/open-mmlab/mmpose/pull/812)) jin-s13
- Support None as target weights in losses ([\829](https://github.com/open-mmlab/mmpose/pull/829)) Ezra-Yu
- Move process_mmdet_results into inference.py ([\831](https://github.com/open-mmlab/mmpose/pull/831)) ly015
- Update resource limit ([\783](https://github.com/open-mmlab/mmpose/pull/783)) jin-s13
- Use COCO 2D pose model in 3D demo examples ([\785](https://github.com/open-mmlab/mmpose/pull/785)) ly015
- Change model zoo titles in the doc from center-aligned to left-aligned ([\792](https://github.com/open-mmlab/mmpose/pull/792), [\#797](https://github.com/open-mmlab/mmpose/pull/797)) ly015
- Support MIM ([\706](https://github.com/open-mmlab/mmpose/pull/706), [\#794](https://github.com/open-mmlab/mmpose/pull/794)) ly015
- Update out-of-date configs ([\827](https://github.com/open-mmlab/mmpose/pull/827)) jin-s13
- Remove opencv-python-headless dependency by albumentations ([\833](https://github.com/open-mmlab/mmpose/pull/833)) ly015
- Update QQ QR code in README_CN.md ([\832](https://github.com/open-mmlab/mmpose/pull/832)) ly015