Ed Miliband pledged to "call time on clock-watch care" by taking action to end the practice of visits lasting just 15 minutes or less.
He said Labour would work with cash-strapped councils to ensure longer slots were guaranteed and improve conditions for "exploited" carers.
It is one of the recommendations of a study carried out for him by Labour peer Baroness Kingsmill into the impact of poor industry standards on users.
According to separate figures obtained by the party, up to half of care providers may not be paying staff the national minimum wage.
Shadow care minister Liz Kendall said a freedom of information response showed 50% of those inspected by HM Revenue and Customs failed in some way and called on ministers to name and shame the culprits.
Baroness Kingsmill found 220,000 carers were effectively paid less than the minimum wage and more than 300,000 are on zero-hours contracts.
Fewer than three in five were given specialised training in dealing with dementia or stroke-related conditions nearly a third received no regular training, she said.
Among her other recommendations are l icensing care managers, forcing the Care Quality Commission watchdog to refer suspected minimum wage breaches to the authorities and the introduction of a "care charter" to enforce minimum standards.
Mr Miliband said the report " shows that the army of care workers, who carry out some of the most important work anyone can do looking after parents, grandparents and the most vulnerable in our society, are often exploited with real consequences for those they care for.
"I have already set out detailed policy to strengthen the enforcement of the National Minimum Wage and end exploitation of zero hours contracts.
"I know that councils are under enormous pressure from reductions in central government funding.
"But I am also determined that a Labour government will call time on clock-watch care. We will work with councils and care providers to end this practice."
Ms Kendall said the "shocking" scale of minimum wage breaches required immediate Government action.
"Over a million pounds is now owed to care workers - yet neither HMRC nor the Government will tell us which companies are responsible or how many people have been affected," she said.
"It is totally unacceptable that companies are failing to meet their legal duties. The Government must immediately name the companies concerned, HMRC must take action in each case where it finds non-compliance, and dedicated care workers must get what they are owed."
Baroness Kingsmill said: "Care for elderly and disabled people is a major issue for the mid-21st Century. We are likely to live longer and a large number of is will require care in our final years.
"Improving conditions for care workers and care recipients is a journey: we need to act now, but we need long term change and to truly value care as essential to the well-being of some of the most vulnerable people in society."
Richard Hawkes, chair of the Care and Support Alliance, a coalition of 75 care organisations, said: "Our members regularly hear from older and disabled people - and their carers - that getting support is a battle and that the help they receive isn't up to scratch.
"Sitting behind the issues of exploitation in care is a story of chronic under-funding that has seen councils ration and restrict care and has undermined commissioning and provision of high-quality care that puts the person first."
Care and support minister Norman Lamb said: "We want to create a fairer society where everyone gets better care. To do this we need a skilled, valued and fairly paid workforce that has enough time to give people safe, compassionate care.
"As a Government we're taking tougher action on employers who don't pay the minimum wage by naming and shaming companies and helping staff get back hundreds of thousands of pounds in pay owed to them.
"We're also working with councils to clamp down on rushed visits and ensure they work with providers that have fair pay, terms and conditions for their staff."
Jane Harris, managing director of campaigns and engagement at the charity Leonard Cheshire Disability, said: " We are delighted that the Kingsmill review has recognised the scandal of 'flying' 15-minute care visits.
"People who need help with personal tasks like going to the loo or eating should not be rushed because of squeezed care visits. Disabled and older people and their care workers all suffer from them.
"We should show more appreciation for the dedicated workers who day in, day out care for disabled and older people. The vast majority are incredibly dedicated and talented and thousands of people rely on their support.
"Hopefully this report will stimulate debate about both how we can improve care, but also about how society celebrates and values the amazing people who already provide fantastic support every day."