Question: Why do we need to stay active during lockdown for COVID-19

Answer passage (source: WHO):
page_title: Q&A: Be Active during COVID-19
section_headers: How do I stay active in and around the home?
section_content: Try and reduce long periods of time spent sitting , whether for work,
studying, watching TV, reading, or using social media or playing games using
screens. Reduce sitting for long periods by taking short 3-5 minute breaks
every 20-30 minutes. Simply stand up and stretch or even better, take a walk
around the house, up and down the stairs, or into the garden. By just moving
around and stretching you can improve your health and wellbeing. For more
ideas and illustrations of healthy stretches see
here.
Set up a regular routine to be active every day , by planning a physical
activity or exercise break either by yourself, by joining an online class, or
by setting up a time to be active online with your friends or colleagues.
Making a specific time to be active helps ensure you get your daily physical
activity. Put the time in your diary, and it will help remind you. Stick with
it, as this will help you build a regular routine, and help you adjust to new
ways of working, study and family life under COVID-19 restrictions
Be active with your family and friends , **** connecting with others
can help you and your family in the home and elsewhere spend time together and
be active. Planning time to be active with your children with active games at
home, walks in the parks, or cycling can be a way the whole family can relax,
be together and be active and healthy whilst at home.
Set yourself and your family Be Active goals, by choosing a specific type
of activity, time of day and/or number of minutes you will do every day. Get
each family member to choose their own goal which sets a bit of a challenge
but is realistic with help from family or friends and motivation. Record your
progress on a weekly activity chart and, if you think it would help, reward
yourself with something you value.
http://www.euro.who.int/en/health-topics/health-emergencies/coronavirus-
covid-19/novel-coronavirus-2019-ncov-technical-guidance/stay-physically-
active-during-self-
quarantine/_recache?fbclid=IwAR2RQYVYBnmpDCMjBwqmoz0hZxzmit_9yKzXu6ZhjGNywRTEzWOUQefU8V0
More physical activity ideas to help you stay active
For Infants under 1 year of age ****

Spend regular time doing floor-based play with your baby in a prone position (‘tummy time’) and spread this throughout the day while baby is awake.

For Children under 5 years of age ****

Active play in and around the home – invent games which involve being active and can develop skills in throwing, catching, kicking, as well as developing posture and balance.
Active play and games where children get out of breath, such as running around, skipping and jumping.  

For Children and adolescents aged 5-17 years ****

Active games and active play with family. ****
Join in online active games or activity classes, also look for online physical education classes as well as exercise routines suitable for adolescents.
Set up playground games indoors such as Jump rope and hop-scotch – make up new games and challenges that involve being active. 
Learn a new skill – for example try an learn to juggle. 
Encourage doing some muscle strength training activities such as lifting weights or use improvised weight such as bottles full of water or sand.

For Adults ****

Climb up the stairs as much as you can, think of it as an opportunity to be active.
Use household chores as a way to be more physical activity. 
Join in an online exercise class or make up your own routine to music you enjoy that uses the major muscle groups and raises you heart rate. 
Do some muscle strengthening activities such as lifting weights or improvise using full bottles of water or simply use your own body weight and do sets of press ups, sit ups and squats. 
Make time for fun, such as dancing to music.

Where to get more help and information
For more ideas use internet search platforms and check out social media for
suggestions and access to free resources suitable for children of all ages and
adults of all fitness and abilities.

Reviewer feedback on this answer:
This information does not answer the question. This answer contains comprehensive list of activities people can do at home to stay active. It does not provide any information on why people need to stay active during covid-19 lockdown as asked in the question.
Great answer, this give tips as well as how to for they different ages groups
This answers what we need to do to stay active but does not answer why we need to stay active.

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